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Additions to the NASA Aeronautics and Space Database as of 10/12/2009
20090034082 Commonwealth Scientific and Industrial Research Organization, Linfield, Australia
Development and Evaluation of Sensor Concepts for Ageless Aerospace Vehicles: Report 5 - Phase 2 Implementation of the Concept Demonstrator
Batten, Adam; Dunlop, John; Edwards, Graeme; Farmer, Tony; Gaffney, Bruce; Hedley, Mark; Hoschke, Nigel; Isaacs, Peter; Johnson, Mark; Lewis, Chris; Murdoch, Alex; Poulton, Geoff; Price, Don; Prokopenko, Mikhail; Sharp, Ian; Scott, Andrew; Valencia, Philip; Wang, Peter; Whitnall, Denis; September 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 939904.05.07
Report No.(s): NASA/CR-2009-215931; LF99-7916; L-71308D; TIPP 2056; Copyright; Avail.: CASI: A04, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090034082
This report describes the second phase of the implementation of the Concept Demonstrator experimental test-bed system containing sensors and processing hardware distributed throughout the structure, which uses multi-agent algorithms to characterize impacts and determine a suitable response to these impacts. This report expands and adds to the report of the first phase implementation. The current status of the system hardware is that all 192 physical cells (32 on each of the 6 hexagonal prism faces) have been constructed, although only four of these presently contain data-acquisition sub-modules to allow them to acquire sensor data. Impact detection.. location and severity have been successfully demonstrated. The software modules for simulating cells and controlling the test-bed are fully operational. although additional functionality will be added over time. The visualization workstation displays additional diagnostic information about the array of cells (both real and simulated) and additional damage information. Local agent algorithms have been developed that demonstrate emergent behavior of the complex multi-agent system, through the formation of impact damage boundaries and impact networks. The system has been shown to operate well for multiple impacts. and to demonstrate robust reconfiguration in the presence of damage to numbers of cells.
Author
ALGORITHMS; DATA ACQUISITION; TEST STANDS; MODULES; IMPACT DAMAGE; DISPLAY DEVICES; COMPUTER PROGRAMS; COMPLEX SYSTEMS; PROVING
20090034086 NASA Dryden Flight Research Center, Edwards, CA, United States
Further Development of Ko Displacement Theory for Deformed Shape Predictions of Nonuniform Aerospace Structures
Ko, William L.; Fleischer, Van Tran; September 2009; In English; Original contains black and white illustrations
Report No.(s): NASA/TP-2009-214643; H-2889; DFRC-781; No Copyright; Avail.: CASI: A05, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090034086
The Ko displacement theory previously formulated for deformed shape predictions of nonuniform beam structures is further developed mathematically. The further-developed displacement equations are expressed explicitly in terms of geometrical parameters of the beam and bending strains at equally spaced strain-sensing stations along the multiplexed fiber-optic sensor line installed on the bottom surface of the beam. The bending strain data can then be input into the displacement equations for calculations of local slopes, deflections, and cross-sectional twist angles for generating the overall deformed shapes of the nonuniform beam. The further-developed displacement theory can also be applied to the deformed shape predictions of nonuniform two-point supported beams, nonuniform panels, nonuniform aircraft wings and fuselages, and so forth. The high degree of accuracy of the further-developed displacement theory for nonuniform beams is validated by finite-element analysis of various nonuniform beam structures. Such structures include tapered tubular beams, depth-tapered unswept and swept wing boxes, width-tapered wing boxes, and double-tapered wing boxes, all under combined bending and torsional loads. The Ko displacement theory, combined with the fiber-optic strain-sensing system, provide a powerful tool for in-flight deformed shape monitoring of unmanned aerospace vehicles by ground-based pilots to maintain safe flights.
Author
SLOPES; DISPLACEMENT; DEFORMATION; BEAMS (SUPPORTS); STRUCTURAL ENGINEERING; IN-FLIGHT MONITORING; FINITE ELEMENT METHOD
20090034167 Boeing Co., Huntington Beach, CA, United States
Damage Arresting Composites for Shaped Vehicles
Velicki, Alex; September 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): NNL07AA48CWBS 561581.02.08.07.15.03; 4200208122
Report No.(s): NASA/CR-2009-215932; LF99-8391; Copyright; Avail.: CASI: A05, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090034167
This report describes the development of a novel structural solution that addresses the demanding fuselage loading requirements for the Hybrid Wing or Blended Wing Body configurations that are described in NASA NRA subtopic A2A.3, "Materials and Structures for Wing Components and Non-Circular Fuselage." The phase I portion of this task includes a comprehensive finite element model-based structural sizing exercise performed using the BWB airplane configuration to generate internal loads and fuselage panel weights for an advanced Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) structural concept. An accompanying element-level test program is also described which substantiates the analytical results and calculation methods used in the trade study. The phase II plan for the continuation of this research is also included herein.
Author
BLENDED-WING-BODY CONFIGURATIONS; AERODYNAMIC CONFIGURATIONS; FUSELAGES; PULTRUSION; LOADS (FORCES); DAMAGE
20090034177 NASA Goddard Space Flight Center, Greenbelt, MD, United States
Design Aspects of the VLBI2010 System - Progress Report of the IVS VLBI2010 Committee
Petrachenko, Bill; Niell, Arthur; Behrend, Dirk; Corey, Brian; Boehm, Johannes; Chralot, Patrick; Collioud, Arnaud; Gipson, John; Haas, Ruediger; Hobiger, Thomas; Koyama, Yasuhiro; MacMillan, Dan; Malkin, Zinvoy; Nilsson, Tobias; Pany, Andrea; Tuccari, Gino; Whitney, Alan; Wresnik, Joerg; June 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): NNG05HY04CP18404-N10
Report No.(s): NASA/TM-2009-214180; 200901964; Copyright; Avail.: CASI: A04, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090034177
This report summarizes the progress made in developing the next generation VLBI system, dubbed the VLBI2010 system. The VLBI2010 Committee of the International VLBI Service for Geodesy and Astrometry (IVS) worked on the design aspects of the new system. The report covers Monte Carlo simulations showing the impact of the new operating modes on the final products. A section on system considerations describes the implications for the VLBI2010 system parameters by considering the new modes and system-related issues such as sensitivity, antenna slew rate, delay measurement error. RF1, frequency requirements, antenna deformation, and source structure corrections_ This is followed by a description of all major subsystems and recommendations for the network, station. and antenna. Then aspects of the feed, polarization processing. calibration, digital back end, and correlator subsystems are covered. A section is dedicated to the NASA. proof-of-concept demonstration. Finally, sections tm operational considerations, on risks and fallback options, and on the next steps complete the report.
Author
VERY LONG BASE INTERFEROMETRY; GEODESY; ASTROMETRY; DIGITAL SYSTEMS; CALIBRATING; FREQUENCIES; PROVING; CORRELATORS
Additions to the NASA Aeronautics and Space Database as of 10/13/2009
20090034255 NASA Dryden Flight Research Center, Edwards, CA, United States
Stability and Control Analysis of the F-15B Quiet SpikeTM Aircraft
McWherter, Shaun C.; Moua, Cheng M.; Gera, Joseph; Cox, Timothy H.; August 2009; In English; Original contains color illustrations
Contract(s)/Grant(s): NAS4-02021
Report No.(s): NASA/TM-2009-214651; H-2956; DFRC-654; Copyright; Avail.: CASI: A04, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090034255
The primary purpose of the Quiet Spike(TradeMark) flight research program was to analyze the aerodynamic, structural, and mechanical proof-of-concept of a large multi-stage telescoping nose spike installed on the National Aeronautics and Space Administration Dryden Flight Research Center (Edwards, California) F-15B airplane. This report describes the preflight stability and control analysis performed to assess the effect of the spike on the stability, controllability, and handling qualities of the airplane; and to develop an envelope expansion approach to maintain safety of flight. The overall flight test objective was to collect flight data to validate the spike structural dynamics and loads model up to Mach 1.8. Other objectives included validating the mechanical feasibility of a morphing fuselage at operational conditions and determining the near-field shock wave characterization. The two main issues relevant to the stability and control objectives were the effects of the spike-influenced aerodynamics on the F-15B airplane flight dynamics, and the air data and angle-of-attack sensors. The analysis covered the sensitivity of the stability margins, and the handling qualities due to aerodynamic variation and the maneuvering limitations of the F-15B Quiet Spike configuration. The results of the analysis and the implications for the flight test program are also presented.
Author
STABILITY TESTS; AERODYNAMICS; DYNAMIC STRUCTURAL ANALYSIS; FLIGHT TESTS; ANGLE OF ATTACK; SPIKES (AERODYNAMIC CONFIGURATIONS); AEROMANEUVERING
Additions to the NASA Aeronautics and Space Database as of 11/05/2009
20090036992 NASA Ames Research Center, Moffett Field, CA, United States
On Organization of Information: Approach and Early Work
Degani, Asaf; Jorgensen, Charles C.; Iverson, David; Shafto, Michael; Olson, Leonard; May 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 292487.01.01.02
Report No.(s): NASA/TM-2009-215368; ARC-E-DAA-TN585; No Copyright; Avail.: CASI: A06, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090036992
In this report we describe an approach for organizing information for presentation and display. "e approach stems from the observation that there is a stepwise progression in the way signals (from the environment and the system under consideration) are extracted and transformed into data, and then analyzed and abstracted to form representations (e.g., indications and icons) on the user interface. In physical environments such as aerospace and process control, many system components and their corresponding data and information are interrelated (e.g., an increase in a chamber s temperature results in an increase in its pressure). "ese interrelationships, when presented clearly, allow users to understand linkages among system components and how they may affect one another. Organization of these interrelationships by means of an orderly structure provides for the so-called "big picture" that pilots, astronauts, and operators strive for.
Author
AEROSPACE SYSTEMS; INFORMATION SYSTEMS; LINKAGES
20090037028 NASA Glenn Research Center, Cleveland, OH, United States
A Theoretical Investigation of Composite Overwrapped Pressure Vessel (COPV) Mechanics Applied to NASA Full Scale Tests
Thesken, John C.; Murthy, Pappu L. N.; Phoenix, S. L.; Greene, N.; Palko, Joseph L.; Eldridge, Jeffrey; Sutter, James; Saulsberry, R.; Beeson, H.; September 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 869021.03.03.02.01
Report No.(s): NASA/TM-2009-215684; E-17056; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090037028
A theoretical investigation of the factors controlling the stress rupture life of the National Aeronautics and Space Administration's (NASA) composite overwrapped pressure vessels (COPVs) continues. Kevlar (DuPont) fiber overwrapped tanks are of particular concern due to their long usage and the poorly understood stress rupture process in Kevlar filaments. Existing long term data show that the rupture process is a function of stress, temperature and time. However due to the presence of a load sharing liner, the manufacturing induced residual stresses and the complex mechanical response, the state of actual fiber stress in flight hardware and test articles is not clearly known. This paper is a companion to a previously reported experimental investigation and develops a theoretical framework necessary to design full-scale pathfinder experiments and accurately interpret the experimentally observed deformation and failure mechanisms leading up to static burst in COPVs. The fundamental mechanical response of COPVs is described using linear elasticity and thin shell theory and discussed in comparison to existing experimental observations. These comparisons reveal discrepancies between physical data and the current analytical results and suggest that the vessel s residual stress state and the spatial stress distribution as a function of pressure may be completely different from predictions based upon existing linear elastic analyses. The 3D elasticity of transversely isotropic spherical shells demonstrates that an overly compliant transverse stiffness relative to membrane stiffness can account for some of this by shifting a thin shell problem well into the realm of thick shell response. The use of calibration procedures are demonstrated as calibrated thin shell model results and finite element results are shown to be in good agreement with the experimental results. The successes reported here have lead to continuing work with full scale testing of larger NASA COPV hardware.
Author
PRESSURE VESSELS; COMPOSITE WRAPPING; ELASTIC PROPERTIES; FULL SCALE TESTS; RESIDUAL STRESS; SHELL THEORY; DEFORMATION
20090037048 NASA Glenn Research Center, Cleveland, OH, United States
An Overview of Prognosis Health Management Research at Glenn Research Center for Gas Turbine Engine Structures With Special Emphasis on Deformation and Damage Modeling
Arnold, Steven M.; Goldberg, Robert K.; Lerch, Bradley A.; Saleeb, Atef F.; September 2009; In English; Annual Conference of the Prognostics and Health Management Society 2009, 27 Sep. -1 Oct. 2009, San Diego, CA, United States; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 645846.02.02.03.03
Report No.(s): NASA/TM-2009-215827; E-17089; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090037048
Herein a general, multimechanism, physics-based viscoelastoplastic model is presented in the context of an integrated diagnosis and prognosis methodology which is proposed for structural health monitoring, with particular applicability to gas turbine engine structures. In this methodology, diagnostics and prognostics will be linked through state awareness variable(s). Key technologies which comprise the proposed integrated approach include (1) diagnostic/detection methodology, (2) prognosis/lifing methodology, (3) diagnostic/prognosis linkage, (4) experimental validation, and (5) material data information management system. A specific prognosis lifing methodology, experimental characterization and validation and data information management are the focal point of current activities being pursued within this integrated approach. The prognostic lifing methodology is based on an advanced multimechanism viscoelastoplastic model which accounts for both stiffness and/or strength reduction damage variables. Methods to characterize both the reversible and irreversible portions of the model are discussed. Once the multiscale model is validated the intent is to link it to appropriate diagnostic methods to provide a full-featured structural health monitoring system.
Author
GAS TURBINE ENGINES; MULTISCALE MODELS; PROGNOSIS; VISCOELASTICITY; ELASTOPLASTICITY; DAMAGE; DEFORMATION; DIAGNOSIS
Additions to the NASA Aeronautics and Space Database as of 11/06/2009
20090037083 NASA Glenn Research Center, Cleveland, OH, United States
COMPASS Final Report: Near Earth Asteroids Rendezvous and Sample Earth Returns (NEARER)
Oleson, Steven R.; McGuire, Melissa L.; September 2009; In English; (NEARER) Near Earth Asteroids Rendezvous and Sample Earth Returns (NEARER)/ 31st IEPC, 20-24 Sep. 2009, Ann Arbor, MI, United States; Original contains color illustrations
Contract(s)/Grant(s): WBS 346620.02.01.01.03.02
Report No.(s): NASA/TM-2009-215825; CD-2008-28; E-17087; No Copyright; Avail.: CASI: A05, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090037083
In this study, the Collaborative Modeling for Parametric Assessment of Space Systems (COMPASS) team completed a design for a multi-asteroid (Nereus and 1996 FG3) sample return capable spacecraft for the NASA In-Space Propulsion Office. The objective of the study was to support technology development and assess the relative benefits of different electric propulsion systems on asteroid sample return design. The design uses a single, heritage Orion solar array (SA) (approx.6.5 kW at 1 AU) to power a single NASA Evolutionary Xenon Thruster ((NEXT) a spare NEXT is carried) to propel a lander to two near Earth asteroids. After landing and gathering science samples, the Solar Electric Propulsion (SEP) vehicle spirals back to Earth where it drops off the first sample s return capsule and performs an Earth flyby to assist the craft in rendezvousing with a second asteroid, which is then sampled. The second sample is returned in a similar fashion. The vehicle, dubbed Near Earth Asteroids Rendezvous and Sample Earth Returns (NEARER), easily fits in an Atlas 401 launcher and its cost estimates put the mission in the New Frontier s (NF's) class mission.
Author
ASTEROIDS; SOLAR ELECTRIC PROPULSION; SAMPLE RETURN MISSIONS; PROPULSION SYSTEM CONFIGURATIONS; SYSTEMS ENGINEERING; FLYBY MISSIONS; PROPULSION SYSTEM PERFORMANCE; ELECTRIC PROPULSION
Additions to the NASA Aeronautics and Space Database as of 11/10/2009
20090037329 NASA Langley Research Center, Hampton, VA, United States
From Verified Models to Verifiable Code
Lensink, Leonard; Munoz, Cesar A.; Goodloe, Alwyn E.; October 2009; In English; Original contains color illustrations
Contract(s)/Grant(s): NCC1-02043NNX08AE37AWBS 645846.02.07.07.15.03
Report No.(s): NASA/TM-2009-215943; L-19766; LF99-9439; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090037329
Declarative specifications of digital systems often contain parts that can be automatically translated into executable code. Automated code generation may reduce or eliminate the kinds of errors typically introduced through manual code writing. For this approach to be effective, the generated code should be reasonably efficient and, more importantly, verifiable. This paper presents a prototype code generator for the Prototype Verification System (PVS) that translates a subset of PVS functional specifications into an intermediate language and subsequently to multiple target programming languages. Several case studies are presented to illustrate the tool's functionality. The generated code can be analyzed by software verification tools such as verification condition generators, static analyzers, and software model-checkers to increase the confidence that the generated code is correct.
Author
PROGRAMMING LANGUAGES; FUNCTIONAL DESIGN SPECIFICATIONS; DIGITAL SYSTEMS; PROGRAM VERIFICATION (COMPUTERS); ERRORS
Additions to the NASA Aeronautics and Space Database as of 11/11/2009
20090037432 NASA Langley Research Center, Hampton, VA, United States
Coupled Neutron Transport for HZETRN
Slaba, Tony C.; Blattnig, Steve R.; October 2009; In English; Original contains black and white illustrations
Contract(s)/Grant(s): WBS 65149.02.07.01
Report No.(s): NASA/TP-2009-215941; L-19769; LF99-9539; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090037432
Exposure estimates inside space vehicles, surface habitats, and high altitude aircrafts exposed to space radiation are highly influenced by secondary neutron production. The deterministic transport code HZETRN has been identified as a reliable and efficient tool for such studies, but improvements to the underlying transport models and numerical methods are still necessary. In this paper, the forward-backward (FB) and directionally coupled forward-backward (DC) neutron transport models are derived, numerical methods for the FB model are reviewed, and a computationally efficient numerical solution is presented for the DC model. Both models are compared to the Monte Carlo codes HETC-HEDS, FLUKA, and MCNPX, and the DC model is shown to agree closely with the Monte Carlo results. Finally, it is found in the development of either model that the decoupling of low energy neutrons from the light particle transport procedure adversely affects low energy light ion fluence spectra and exposure quantities. A first order correction is presented to resolve the problem, and it is shown to be both accurate and efficient.
Author
NEUTRONS; ENERGY TRANSFER; EXTRATERRESTRIAL RADIATION; EXPOSURE; DECOUPLING; ENERGY SPECTRA; LIGHT IONS
Additions to the NASA Aeronautics and Space Database as of 11/13/2009
20090037582 NASA Langley Research Center, Hampton, VA, United States
Shuttle Gaseous Hydrogen Venting Risk from Flow Control Valve Failure
Drummond, J. Philip; Baurle, Robert A.; Gafney, Richard L.; Norris, Andrew T.; Pellett, Gerald L.; Rock, Kenneth E.; October 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 378343.10.01.05.08
Report No.(s): NASA/TM-2009-215942; LF99-8616; L-19767; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090037582
This paper describes a series of studies to assess the potential risk associated with the failure of one of three gaseous hydrogen flow control valves in the orbiter's main propulsion system during the launch of Shuttle Endeavour (STS-126) in November 2008. The studies focused on critical issues associated with the possibility of combustion resulting from release of gaseous hydrogen from the external tank into the atmosphere during assent. The Shuttle Program currently assumes hydrogen venting from the external tank will result in a critical failure. The current effort was conducted to increase understanding of the risk associated with venting hydrogen given the flow control valve failure scenarios being considered in the Integrated In-Flight Anomaly Investigation being conducted by NASA.
Author
CONTROL VALVES; HYDROGEN; VENTING; AEROSPACE SAFETY; ENDEAVOUR (ORBITER); RISK MANAGEMENT; FAILURE ANALYSIS
Additions to the NASA Aeronautics and Space Database as of 11/19/2009
20090038656 NASA Langley Research Center, Hampton, VA, United States
NASA Patent Abstracts Bibliography: A Continuing Bibliography Supplement 70
October 2009; In English; Original contains black and white illustrations
Report No.(s): NASA/SP-2009-7039/SUPPL70; No Copyright; Avail.: CASI: A04, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090038656
Several thousand inventions result each year from research supported by the National Aeronautics and Space Administration. NASA seeks patent protection on inventions to which it has title if the invention has important use in government programs or significant commercial potential. These inventions cover a broad range of technologies and include many that have useful and valuable commercial application. NASA inventions best serve the interests of the United States when their benefits are available to the public. In many instances, the granting of nonexclusive or exclusive licenses for the practice of these inventions may assist in the accomplishment of this objective. This bibliography is published as a service to companies, firms, and individuals seeking new, licensable products for the commercial market. The NASA Patent Abstracts Bibliography is an annual NASA publication containing comprehensive abstracts of NASA-owned inventions covered by U.S. patents. The citations included were originally published in NASA s Scientific and Technical Aerospace Reports (STAR). The citations published in this issue cover the period October 2008 through September 2009. The subjects covered include the NASA Scope and Subject Category Guide s 10 broad subject divisions separated further into 76 specific categories. However, not all categories contain citations during the date range of this issue; therefore, the Table of Contents does not include all divisions and categories. Each citation includes an abstract and, when available, a key illustration taken from the patent or application for patent. Also when available, citations include a link to the full-text document online.
Author
INVENTIONS; ABSTRACTS; TECHNOLOGY UTILIZATION; PATENT APPLICATIONS
20090038672 Northrop Grumman Corp., Redondo Beach, CA, United States
Use of Cumulative Degradation Factor Prediction and Life Test Result of the Thruster Gimbal Assembly Actuator for the Dawn Flight Project
Lo, C. John; Brophy, John R.; Etters, M. Andy; Ramesham, Rajeshuni; Jones, William R., Jr.; Jansen, Mark J.; October 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): NNC07JF14TWBS 431731.04.01.03
Report No.(s): NASA/CR-2009-215681; E-17052; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090038672
The Dawn Ion Propulsion System is the ninth project in NASA s Discovery Program. The Dawn spacecraft is being developed to enable the scientific investigation of the two heaviest main-belt asteroids, Vesta and Ceres. Dawn is the first mission to orbit two extraterrestrial bodies, and the first to orbit a main-belt asteroid. The mission is enabled by the onboard Ion Propulsion System (IPS) to provide the post-launch delta-V. The three Ion Engines of the IPS are mounted on Thruster Gimbal Assembly (TGA), with only one engine operating at a time for this 10-year mission. The three TGAs weigh 14.6 kg.
Author
VESTA ASTEROID; ION PROPULSION; ACTUATORS; THERMOGRAVIMETRY; ION ENGINES
20090038700 NASA Glenn Research Center, Cleveland, OH, United States
Large Eddy Simulation of Transonic Flow Field in NASA Rotor 37
Hah, Chunill; September 2009; In English; 47th Aerospace Sciences Meeting, 5-8 Jan. 2009, Orlando, FL, United States; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 561581.02.08.03.21.02
Report No.(s): NASA/TM-2009-215627; E-16939; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090038700
The current paper reports on numerical investigations on the flow characteristics in a transonic axial compressor, NASA Rotor 37. The flow field was used previously as a CFD blind test case conducted by American Society of Mechanical Engineers in 1994. Since the CFD blind-test exercise, many numerical studies on the flow field in the NASA Rotor 37 have been reported. Although steady improvements have been reported in both numerical procedure and turbulence closure, it is believed that all the important aspects of the flow field have not been fully explained with numerical studies based on the Reynolds Averaged Navier-Stokes (RANS) solution. Experimental data show large dip in total pressure distribution near the hub at downstream of the rotor at 100% rotor speed. Most original numerical solutions from the blind test exercise did not predict this total pressure deficit correctly. This total pressure deficit at the rotor exit was attributed to a hub corner flow separation by the author. Several subsequent numerical studies with different turbulence closure model also calculated this dip in total pressure rise. Also, several studies attributed this total pressure deficit to a small leakage flow coming from the hub in the test article. As the experimental study cannot be repeated, either explanation cannot be validated. The primary purpose of the current investigation is to investigate the transonic flow field with both RANS and a Large Eddy Simulation (LES). The RANS approach gives similar results presented at the original blind test exercise. Although the RANS calculates higher overall total pressure rise, the total pressure deficit near the hub is calculated correctly. The numerical solution shows that the total pressure deficit is due to a hub corner flow separation. The calculated pressure rise from the LES agrees better with the measured total pressure rise especially near the casing area where the passage shock interacts with the tip clearance vortex and flow becomes unsteady due to this interaction. The LES simulation also calculates the total pressure rise deficit near the hub and it agrees well with the measured data.
Author
TRANSONIC COMPRESSORS; PRESSURE DISTRIBUTION; LARGE EDDY SIMULATION; NAVIER-STOKES EQUATION; COMPUTATIONAL FLUID DYNAMICS; FLOW CHARACTERISTICS; REYNOLDS AVERAGING; SEPARATED FLOW; TURBULENT FLOW; BOUNDARY LAYER SEPARATION
20090038701 NASA Glenn Research Center, Cleveland, OH, United States
Attenuation of FJ44 Turbofan Engine Noise with a Foam-Metal Liner Installed Over-the-Rotor
Sutliff, Daniel L.; Elliott, Dave M.; Jones, Michael G.; Hartley, Thomas C.; September 2009; In English; 30th Aeroacoustics Conference, 11-13 May 2009, Miami, Fl, United States; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 685676.01.03.08.0
Report No.(s): NASA/TM-2009-215666; AIAA Paper 2009-3141; E-17008; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090038701
A Williams International FJ44-3A 3000-lb thrust class turbofan engine was used as a demonstrator for a Foam-Metal Liner (FML) installed in close proximity to the fan. Two FML designs were tested and compared to the hardwall baseline. Traditional single degree-of-freedom liner designs were also evaluated to provide a comparison. Farfield acoustic levels and limited engine performance results are presented in this paper. The results show that the FML achieved up to 5 dB Acoustic Power Level (PWL) overall attenuation in the forward quadrant, equivalent to the traditional liner design. An earlier report presented the test set-up and conditions.
Author
ENGINE NOISE; TURBOFAN ENGINES; SOUND PRESSURE; ACOUSTIC MEASUREMENT; DEGREES OF FREEDOM; LININGS
20090038702 NASA Glenn Research Center, Cleveland, OH, United States
Health Monitoring of a Rotating Disk Using a Combined Analytical-Experimental Approach
Abdul-Aziz, Ali; Woike, Mark R.; Lekki, John D.; Baaklini, George Y.; September 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 645846.02.07.03.11.03
Report No.(s): NASA/TM-2009-215675; E-17038; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090038702
Rotating disks undergo rigorous mechanical loading conditions that make them subject to a variety of failure mechanisms leading to structural deformities and cracking. During operation, periodic loading fluctuations and other related factors cause fractures and hidden internal cracks that can only be detected via noninvasive types of health monitoring and/or nondestructive evaluation. These evaluations go further to inspect material discontinuities and other irregularities that have grown to become critical defects that can lead to failure. Hence, the objectives of this work is to conduct a collective analytical and experimental study to present a well-rounded structural assessment of a rotating disk by means of a health monitoring approach and to appraise the capabilities of an in-house rotor spin system. The analyses utilized the finite element method to analyze the disk with and without an induced crack at different loading levels, such as rotational speeds starting at 3000 up to 10 000 rpm. A parallel experiment was conducted to spin the disk at the desired speeds in an attempt to correlate the experimental findings with the analytical results. The testing involved conducting spin experiments which, covered the rotor in both damaged and undamaged (i.e., notched and unnotched) states. Damaged disks had artificially induced through-thickness flaws represented in the web region ranging from 2.54 to 5.08 cm (1 to 2 in.) in length. This study aims to identify defects that are greater than 1.27 cm (0.5 in.), applying available means of structural health monitoring and nondestructive evaluation, and documenting failure mechanisms experienced by the rotor system under typical turbine engine operating conditions.
Author
TURBINE ENGINES; NONDESTRUCTIVE TESTS; CRACKS; STRUCTURAL FAILURE; FRACTURES (MATERIALS); ROTATING DISKS; ROTORS
Additions to the NASA Aeronautics and Space Database as of 11/20/2009
20090038706 Sest, Inc., Middleburgh Heights, OH, United States; Jet Propulsion Lab., California Inst. of Tech., Pasadena, CA, United States
Effect of Ceramic Ball and Hybrid Stainless Steel Bearing/Wheel Combinations on the Lifetime of a Precision Translation Stage for the SIM Flight Project
Lo, C. John; Klein, Kerry; Jones, William R., Jr.; Jansen, Mark J.; Wemhoner, Jens; October 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): NNC07JF14T; NAS7-03001WBS 431731.04.01.03
Report No.(s): NASA/CR-2009-215682; E-17053; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090038706
A study of hybrid material couples using the Spiral Orbit Tribometer (SOT) was initiated to investigate both lubricated (Pennzane X2000 and Brayco 815Z) and unlubricated Si3N4, 440C SS, Rex 20, Cronidur X30 and X40 plates with Cerbec SN-101-C (Si3N4) and 440C balls. The hybrid wheel/bearing assembly will be used on the Linear Optical Delay Line (LODL) stage as an element of the NASA Space Interferometry Mission (SIM). SIM is an orbiting interferometer linking a pair of telescopes within the spacecraft and, by using an interferometry technique and several precision optical stages, is able to measure the motions of known stars much better than current ground or space based systems. This measurement will provide the data to "infer" the existence of any plants, undetectable by other methods, orbiting these known stars.
Author
BALL BEARINGS; TRIBOMETERS; DELAY LINES; SPACE MISSIONS; INTERFEROMETERS
20090038710 NASA Glenn Research Center, Cleveland, OH, United States
The Case for Distributed Engine Control in Turbo-Shaft Engine Systems
Culley, Dennis E.; Paluszewski, Paul J.; Storey, William; Smith, Bert J.; September 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 561581.02.08.03.17.03
Report No.(s): NASA/TM-2009-215654; AHS 2009 080366; E-16966; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090038710
The turbo-shaft engine is an important propulsion system used to power vehicles on land, sea, and in the air. As the power plant for many high performance helicopters, the characteristics of the engine and control are critical to proper vehicle operation as well as being the main determinant to overall vehicle performance. When applied to vertical flight, important distinctions exist in the turbo-shaft engine control system due to the high degree of dynamic coupling between the engine and airframe and the affect on vehicle handling characteristics. In this study, the impact of engine control system architecture is explored relative to engine performance, weight, reliability, safety, and overall cost. Comparison of the impact of architecture on these metrics is investigated as the control system is modified from a legacy centralized structure to a more distributed configuration. A composite strawman system which is typical of turbo-shaft engines in the 1000 to 2000 hp class is described and used for comparison. The overall benefits of these changes to control system architecture are assessed. The availability of supporting technologies to achieve this evolution is also discussed.
Author
SHAFTS (MACHINE ELEMENTS); ACTIVE CONTROL; TURBINE ENGINES; HELICOPTERS; ENGINE CONTROL; CONTROL SYSTEMS DESIGN; DISTRIBUTED PARAMETER SYSTEMS
20090038711 NASA Glenn Research Center, Cleveland, OH, United States
High Efficiency Nuclear Power Plants Using Liquid Fluoride Thorium Reactor Technology
Juhasz, Albert J.; Rarick, Richard A.; Rangarajan, Rajmohan; October 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 138494.01.04.01
Report No.(s): NASA/TM-2009-215829; AIAA Paper 2009-4565; E-17030-1; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090038711
An overall system analysis approach is used to propose potential conceptual designs of advanced terrestrial nuclear power plants based on Oak Ridge National Laboratory (ORNL) Molten Salt Reactor (MSR) experience and utilizing Closed Cycle Gas Turbine (CCGT) thermal-to-electric energy conversion technology. In particular conceptual designs for an advanced 1 GWe power plant with turbine reheat and compressor intercooling at a 950 K turbine inlet temperature (TIT), as well as near term 100 MWe demonstration plants with TITs of 950 and 1200 K are presented. Power plant performance data were obtained for TITs ranging from 650 to 1300 K by use of a Closed Brayton Cycle (CBC) systems code which considered the interaction between major sub-systems, including the Liquid Fluoride Thorium Reactor (LFTR), heat source and heat sink heat exchangers, turbo-generator machinery, and an electric power generation and transmission system. Optional off-shore submarine installation of the power plant is a major consideration.
Author
FLUORIDES; GAS TURBINES; NUCLEAR POWER PLANTS; REACTOR TECHNOLOGY; SYSTEMS ANALYSIS; THORIUM
20090038726 NASA Langley Research Center, Hampton, VA, United States
LAURA Users Manual: 5.2-43231
Mazaheri, Alireza; Gnoffo, Peter A.; Johnston, Christopher O.; Kleb, Bil; November 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 736466.11.01.07.43.05.01
Report No.(s): NASA/TM-2009-215944; LF99-9703; L-19783; Copyright; Avail.: CASI: A05, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090038726
This users manual provides in-depth information concerning installation and execution of LAURA, version 5. LAURA is a structured, multi-block, computational aerothermodynamic simulation code. Version 5 represents a major refactoring of the original Fortran 77 LAURA code toward a modular structure afforded by Fortran 95. The refactoring improved usability and maintainability by eliminating the requirement for problem-dependent re-compilations, providing more intuitive distribution of functionality, and simplifying interfaces required for multiphysics coupling. As a result, LAURA now shares gas-physics modules, MPI modules, and other low-level modules with the FUN3D unstructured-grid code. In addition to internal refactoring, several new features and capabilities have been added, e.g., a GNU-standard installation process, parallel load balancing, automatic trajectory point sequencing, free-energy minimization, and coupled ablation and flowfield radiation.
Author
AEROTHERMODYNAMICS; ABLATION; FLOW DISTRIBUTION; COMPUTERIZED SIMULATION; UNSTRUCTURED GRIDS (MATHEMATICS); USER MANUALS (COMPUTER PROGRAMS); FREE ENERGY; COMPUTER PROGRAMS
Additions to the NASA Aeronautics and Space Database as of 11/24/2009
20090038973 NASA Dryden Flight Research Center, Edwards, CA, United States
CFD Analysis of Nozzle Jet Plume Effects on Sonic Boom Signature
Bui, Trong T.; September 2009; In English; 47th AIAA Aerospace Sciences meeting, 5-8 Jan. 2009, Orlando, FL, United States; Original contains color and black and white illustrations
Report No.(s): NASA/TM-2009-214650; AIAA Paper 2009-1054; H-2923; DFRC-938; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090038973
A computational fluid dynamics study is conducted to examine nozzle exhaust jet plume effects on the Sonic boom signature of a supersonic aircraft. A simplified axisymmetric nozzle geometry, representative of the nozzle on the NASA Dryden NF-15B Lift and Nozzle Change Effects on Tail Shock research airplane, is considered. The computational fluid dynamics code is validated using available wind-tunnel sonic boom experimental data. The effects of grid size, spatial order of accuracy. grid type, and flow viscosity on the accuracy of the predicted sonic boom pressure signature are quantified. Grid lines parallel to the Mach wave direction are found to give the best results. Second-order accurate upwind methods are required as a minimum for accurate sonic boom simulations. The highly underexpanded nozzle flow is found to provide significantly more reduction in the tail shock strength in the sonic boom N-wave pressure signature than perfectly expanded and overexpanded nozzle flows. A tail shock train in the sonic boom signature is observed for the highly underexpanded nozzle flow. Axisymmetric computational fluid dynamics simulations show the flow physics inside the F-15 nozzle to be nonisentropic and complex.
Author
COMPUTATIONAL FLUID DYNAMICS; NOZZLE FLOW; GAS JETS; NOZZLE GEOMETRY; SONIC BOOMS; WIND TUNNEL TESTS; PLUMES; F-15 AIRCRAFT
20090039036 NASA, Washington, DC, United States
NASA Historical Data Book Volume 7 NASA Launch Systems, Space Transportation/ Human Spaceflight, and Space Science 1989-1998
Rumerman, Judy A.; January 2009; In English; Original contains black and white illustrations
Report No.(s): NASA/SP-2009-4012/VOL7; No Copyright; Avail.: CASI: A99, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090039036
This volume of the NASA Historical Data Book is the seventh in the series that describes NASA s programs and projects. Covering the years 1989 through 1998, it includes the areas of launch systems, human spaceflight, and space science, Each chapter presents information, much of it statistical, addressing funding, management, and details of programs and missions. This decade, which followed the Agency s return to flight after the Challenger accident, was especially productive. Upgraded expendable launch vehicles sent missions into Earth orbit and toward the outer reaches of space; 66 Space Shuttle missions were successfully launched; the Space Station received its first components; and 30 space science missions, most of which met their scientific goals, began returning scientific data to Earth. These events took place in an environment both of international cooperation and one in which NASA learned to make the best use possible of its resources.
Derived from text
HISTORIES; SPACE MISSIONS; SPACE SHUTTLE MISSIONS; NASA SPACE PROGRAMS; MANAGEMENT
Additions to the NASA Aeronautics and Space Database as of 11/26/2009
20090039455 NASA Langley Research Center, Hampton, VA, United States
Validation of Multibody Program to Optimize Simulated Trajectories II Parachute Simulation with Interacting Forces
Raiszadeh, Behzad; Queen, Eric M.; Hotchko, Nathaniel J.; June 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 136905.08.05.04.05.04
Report No.(s): NASA/TP-2009-215765; L-19644; LF99-8627; Copyright; Avail.: CASI: A06, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090039455
A capability to simulate trajectories of multiple interacting rigid bodies has been developed, tested and validated. This capability uses the Program to Optimize Simulated Trajectories II (POST 2). The standard version of POST 2 allows trajectory simulation of multiple bodies without force interaction. In the current implementation, the force interaction between the parachute and the suspended bodies has been modeled using flexible lines, allowing accurate trajectory simulation of the individual bodies in flight. The POST 2 multibody capability is intended to be general purpose and applicable to any parachute entry trajectory simulation. This research paper explains the motivation for multibody parachute simulation, discusses implementation methods, and presents validation of this capability.
Author
TRAJECTORIES; PARACHUTES
Additions to the NASA Aeronautics and Space Database as of 11/30/2009
20090039500 NASA Glenn Research Center, Cleveland, OH, United States
Synthetic and Biomass Alternate Fueling in Aviation
Hendricks, R.C.; Bushnell, D.M.; October 2009; In English
Contract(s)/Grant(s): WBS 561581.02.08.03.16.03
Report No.(s): NASA/TM-2009-215665; E-16865-1; No Copyright; Avail.: CASI: A02, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090039500
Worldwide, aviation alone uses 85 to 95 billion gallons of nonrenewable fossil fuel per year (2008). General transportation fueling can accommodate several different fuels; however, aviation fuels have very specific requirements. Biofuels have been flight demonstrated, are considered renewable, have the capacity to become "drop-in" replacements for Jet-A fuel, and solve the CO2 climate change problem. The major issue is cost; current biomass biofuels are not economically competitive. Biofuel feedstock sources being researched are halophytes, algae, cyanobacteria, weeds-to-crops, wastes with contingent restraints on use of crop land, freshwater, and climate change. There are five major renewable energy sources: solar thermal, solar photovoltaic, wind, drilled geothermal and biomass, each of which have an order of magnitude greater capacity to meet all energy needs. All five address aspects of climate change; biomass has massive potential as an energy fuel feedstock.
Author
AIRCRAFT FUELS; BIOMASS; RENEWABLE ENERGY; PHOTOVOLTAIC CELLS; FOSSIL FUELS; CLIMATE CHANGE
20090039501 NASA Glenn Research Center, Cleveland, OH, United States
Gear Fault Detection Effectiveness as Applied to Tooth Surface Pitting Fatigue Damage
Lewicki, David G.; Dempsey, Paula J.; Heath, Gregory F.; Shanthakumaran, Perumal; October 2009; In English; The AHS 65th Annual Forum and Technology Display, 27 - 29 May 2009, Grapevine, Texas, United States; Original contains color and black and white illustrations
Contract(s)/Grant(s): 877868.02.07.03.01.01.02
Report No.(s): NASA/TM-2009-215667; E-17009; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090039501
A study was performed to evaluate fault detection effectiveness as applied to gear tooth pitting fatigue damage. Vibration and oil-debris monitoring (ODM) data were gathered from 24 sets of spur pinion and face gears run during a previous endurance evaluation study. Three common condition indicators (RMS, FM4, and NA4) were deduced from the time-averaged vibration data and used with the ODM to evaluate their performance for gear fault detection. The NA4 parameter showed to be a very good condition indicator for the detection of gear tooth surface pitting failures. The FM4 and RMS parameters performed average to below average in detection of gear tooth surface pitting failures. The ODM sensor was successful in detecting a significant amount of debris from all the gear tooth pitting fatigue failures. Excluding outliers, the average cumulative mass at the end of a test was 40 mg.
Author
GEARS; FAULT DETECTION; FATIGUE (MATERIALS); GEAR TEETH; VIBRATION; OILS; FAILURE
Additions to the NASA Aeronautics and Space Database as of 12/01/2009
20090039962 NASA Glenn Research Center, Cleveland, OH, United States
Designing of a Fleet-Leader Program for Carbon Composite Overwrapped Pressure Vessels
Murthy, Pappu L.N.; Phoenix, S. Leigh; October 2009; In English; 50th Structures, Structural Dynamics, and Materials Conference, 4 - 7 May 2009, Palm Springs, California, United States
Contract(s)/Grant(s): WBS 869021.03.03.02.01
Report No.(s): NASA/TM-2009-215685; AIAA Paper 2009-2517; E-17057; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090039962
Composite Overwrapped Pressure Vessels (COPVs) are often used for storing pressurant gases on board spacecraft when mass saving is a prime requirement. Substantial weight savings can be achieved compared to all metallic pressure vessels. For example, on the space shuttle, replacement of all metallic pressure vessels with Kevlar COPVs resulted in a weight savings of about 30 percent. Mass critical space applications such as the Ares and Orion vehicles are currently being planned to use as many COPVs as possible in place of all-metallic pressure vessels to minimize the overall mass of the vehicle. Due to the fact that overwraps are subjected to sustained loads during long periods of a mission, stress rupture failure is a major concern. It is, therefore, important to ascertain the reliability of these vessels by analysis, since it is practically impossible to show by experimental testing the reliability of flight quality vessels. Also, it is a common practice to set aside flight quality vessels as "fleet leaders" in a test program where these vessels are subjected to slightly accelerated operating conditions so that they lead the actual flight vessels both in time and load. The intention of fleet leaders is to provide advanced warning if there is a serious design flaw in the vessels so that a major disaster in the flight vessels can be averted with advance warning. On the other hand, the accelerating conditions must be not so severe as to be prone to false alarms. The primary focus of the present paper is to provide an analytical basis for designing a viable fleet leader program for carbon COPVs. The analysis is based on a stress rupture behavior model incorporating Weibull statistics and power-law sensitivity of life to fiber stress level.
Author
COMPOSITE WRAPPING; PRESSURE VESSELS; WEIBULL DENSITY FUNCTIONS; FILAMENT WINDING; LOADS (FORCES); KEVLAR (TRADEMARK); RELIABILITY; DEFECTS
20090039964 NASA Glenn Research Center, Cleveland, OH, United States
Wind-US User's Guide, Version 2.0
Towne, Charles E.; October 2009; In English; Original contains black and white illustrations
Contract(s)/Grant(s): WBS 599489.02.07.03.03.02.01
Report No.(s): NASA/TM-2009-215804; E-17067; No Copyright; Avail.: CASI: A14, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090039964
Wind-US is a computational platform which may be used to numerically solve various sets of equations governing physical phenomena. Currently, the code supports the solution of the Euler and Navier-Stokes equations of fluid mechanics, along with supporting equation sets governing turbulent and chemically reacting flows. Wind-US is a product of the NPARC Alliance, a partnership between the NASA Glenn Research Center (GRC) and the Arnold Engineering Development Center (AEDC) dedicated to the establishment of a national, applications-oriented flow simulation capability. The Boeing Company has also been closely associated with the Alliance since its inception, and represents the interests of the NPARC User's Association. The "Wind-US User's Guide" describes the operation and use of Wind-US, including: a basic tutorial; the physical and numerical models that are used; the boundary conditions; monitoring convergence; the files that are read and/or written; parallel execution; and a complete list of input keywords and test options.
Author
TURBULENT FLOW; COMPUTATIONAL FLUID DYNAMICS; FLUID MECHANICS; REACTING FLOW; NAVIER-STOKES EQUATION; MATHEMATICAL MODELS; DIFFERENTIAL EQUATIONS; BOUNDARY CONDITIONS
Additions to the NASA Aeronautics and Space Database as of 12/08/2009
20090040594 NASA Dryden Flight Research Center, Edwards, CA, United States
Applications of Ko Displacement Theory to the Deformed Shape Predictions of the Doubly-Tapered Ikhana Wing
Ko, William L.; Richards, W. Lance; Fleischer, Van Tran; October 2009; In English; Original contains color and black and white illustrations
Report No.(s): NASA/TP-2009-214652; DFRC-762; H-3006; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090040594
The Ko displacement theory, formulated for weak nonuniform (slowly changing cross sections) cantilever beams, was applied to the deformed shape analysis of the doubly-tapered wings of the Ikhana unmanned aircraft. The two-line strain-sensing system (along the wingspan) was used for sensing the bending strains needed for the wing-deformed shapes (deflections and cross-sectional twist) analysis. The deflection equation for each strain-sensing line was expressed in terms of the bending strains evaluated at multiple numbers of strain-sensing stations equally spaced along the strain-sensing line. For the preflight shape analysis of the Ikhana wing, the strain data needed for input to the displacement equations for the shape analysis were obtained from the nodal-stress output of the finite-element analysis. The wing deflections and cross-sectional twist angles calculated from the displacement equations were then compared with those computed from the finite-element computer program. The Ko displacement theory formulated for weak nonlinear cantilever beams was found to be highly accurate in the deformed shape predictions of the doubly-tapered Ikhana wing.
Author
DEFORMATION; DISPLACEMENT; SHAPES; SWEPT WINGS; MATHEMATICAL MODELS; PILOTLESS AIRCRAFT
Additions to the NASA Aeronautics and Space Database as of 12/14/2009
20090040686 NASA Glenn Research Center, Cleveland, OH, United States
Effect of Illumination Angle on the Performance of Dusted Thermal Control Surfaces in a Simulated Lunar Environment
Gaier, James R.; October 2009; In English; 39th International Conference on Environmental Systems (ICES), 12-16 Jul. 2009, Savannah, GA, United States; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 119103.04.05.04
Report No.(s): NASA/TM-2009-215647; 2009-01-2420; E-16959; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090040686
JSC-1A lunar simulant has been applied to AZ93 and AgFEP thermal control surfaces on aluminum substrates in a simulated lunar environment. The temperature of these surfaces was monitored as they were heated with a solar simulator using varying angles of incidence and cooled in a 30 K coldbox. Thermal modeling was used to determine the solar absorptivity (a) and infrared emissivity (e) of the thermal control surfaces in both their clean and dusted states. It was found that even a sub-monolayer of dust can significantly raise the a of either type of surface. A full monolayer can increase the a/e ratio by a factor of 3 to 4 over a clean surface. Little angular dependence of the a of pristine thermal control surfaces for both AZ93 and AgFEP was observed, at least until 30 from the surface. The dusted surfaces showed the most angular dependence of a when the incidence angle was in the range of 25 to 35 . Samples with a full monolayer, like those with no dust, showed little angular dependence in a. The e of the dusted thermal control surfaces was within the spread of clean surfaces, with the exception of high dust coverage, where a small increase was observed at shallow angles.
Author
LUNAR ENVIRONMENT; SOLAR SIMULATORS; CONTROL SURFACES; LUNAR DUST; TEMPERATURE CONTROL; LUNAR SOIL; INFRARED RADIATION
20090040687 NASA Glenn Research Center, Cleveland, OH, United States
Regolith Activation on the Lunar Surface and Its Ground Test Simulation
Gaier, James R.; October 2009; In English; 39th International Conference on Environmental Systems (ICES), 12-16 Jul. 2009, Savannah, GA, United States; Original contains black and white illustrations
Contract(s)/Grant(s): WBS 936374.4.08.03
Report No.(s): NASA/TM-2009-215648; 2009-01-2337; E-16960; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090040687
Activation of the surfaces of lunar regolith particles can occur through interactions with solar electromagnetic radiation, solar and galactic particle radiation and micrometeoroid bombardment. An attempt has been made to quantify the relative importance of each of those effects. The effects of these activated surfaces may be to enhance the adhesion and toxicity of the particles. Also key to the importance of activation is the lifetimes of activated states in various environments which is controlled by their passivation rate as well as their activation rate. Although techniques exist to characterize the extent of activation of particles in biological system, it is important to be able to quantify the activation state on the lunar surface, in ground-test vacuum systems, and in habitat atmospheres as well.
Author
LUNAR ROCKS; SOLAR RADIATION; ELECTROMAGNETIC RADIATION; LUNAR SURFACE; MICROMETEOROIDS; GROUND TESTS; ADHESION
20090040689 NASA Glenn Research Center, Cleveland, OH, United States
The Capillary Flow Experiments Aboard the International Space Station: Increments 9-15
Jenson, Ryan M.; Weislogel, Mark M.; Tavan, Noel T.; Chen, Yongkang; Semerjian, Ben; Bunnell, Charles T.; Collicott, Steven H.; Klatte, Jorg; dreyer, Michael E.; September 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): NCC05AA29AWBS 825080.04.02.20.08
Report No.(s): NASA/CR-2009-215586; E-16827; Copyright; Avail.: CASI: A15, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090040689
This report provides a summary of the experimental, analytical, and numerical results of the Capillary Flow Experiment (CFE) performed aboard the International Space Station (ISS). The experiments were conducted in space beginning with Increment 9 through Increment 16, beginning August 2004 and ending December 2007. Both primary and extra science experiments were conducted during 19 operations performed by 7 astronauts including: M. Fincke, W. McArthur, J. Williams, S. Williams, M. Lopez-Alegria, C. Anderson, and P. Whitson. CFE consists of 6 approximately 1 to 2 kg handheld experiment units designed to investigate a selection of capillary phenomena of fundamental and applied importance, such as large length scale contact line dynamics (CFE-Contact Line), critical wetting in discontinuous structures (CFE-Vane Gap), and capillary flows and passive phase separations in complex containers (CFE-Interior Corner Flow). Highly quantitative video from the simply performed flight experiments provide data helpful in benchmarking numerical methods, confirming theoretical models, and guiding new model development. In an extensive executive summary, a brief history of the experiment is reviewed before introducing the science investigated. A selection of experimental results and comparisons with both analytic and numerical predictions is given. The subsequent chapters provide additional details of the experimental and analytical methods developed and employed. These include current presentations of the state of the data reduction which we anticipate will continue throughout the year and culminate in several more publications. An extensive appendix is used to provide support material such as an experiment history, dissemination items to date (CFE publication, etc.), detailed design drawings, and crew procedures. Despite the simple nature of the experiments and procedures, many of the experimental results may be practically employed to enhance the design of spacecraft engineering systems involving capillary interface dynamics.
Author
FLUID FLOW; CAPILLARY FLOW; PREDICTION ANALYSIS TECHNIQUES; NUMERICAL ANALYSIS; INTERNATIONAL SPACE STATION; AEROSPACE ENGINEERING; CORNER FLOW; CREW PROCEDURES (PREFLIGHT); CREW PROCEDURES (INFLIGHT)
Additions to the NASA Aeronautics and Space Database as of 12/15/2009
20090040695 NASA Glenn Research Center, Cleveland, OH, United States
An Experimental Evaluation of the Performance of Two Combination Pitot Pressure Probes
Arend, David J.; Saunders, John D.; October 2009; In English; 47th Aerospace Sciences Meeting, 5-8 Jan. 2009, Orlando, FL, United States; Original contains black and white illustrations
Contract(s)/Grant(s): WBS 561581.02.08.03.21.03
Report No.(s): NASA/TM-2009-215632; AIAA Paper 2009-1073; E-16944; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090040695
Experimental tests have been completed which recorded the ability of two combination steady state and high response time varying Pitot probe designs to accurately measure steady stagnation pressure at a single location in a flow field. Tests were conducted of double-barreled and coannular Prati probes in a 3.5 in. diameter free jet probe calibration facility from Mach 0.1 to 0.9. Geometric symmetry and pitch (-40 deg to 40 deg) and yaw (0 deg to 40 deg) angle actuation were used to fully evaluate the probes. These tests revealed that the double-barreled configuration induced error in its steady state measurement at zero incidence that increased consistently with jet Mach number to 1.1 percent at Mach 0.9. For all Mach numbers, the double-barreled probe nulled at a pitch angle of approximately 7.0 deg and provided inconsistent measurements when yawed. The double-barreled probe provided adequate measurements via both its steady state and high response tubes (within +/- 0.15 percent accuracy) over unacceptable ranges of biased pitch and inconsistent yaw angles which varied with Mach number. By comparison, the coannular probe provided accurate measurements (at zero incidence) for all jet Mach numbers as well as over a flow angularity range which varied from +/- 26.0 deg at Mach 0.3 deg to +/- 14.0 deg at Mach 0.9. Based on these results, the Prati probe is established as the preferred design. Further experimental tests are recommended to document the frequency response characteristics of the Prati probe.
Author
MACH NUMBER; PITCH (INCLINATION); PRESSURE SENSORS; AERODYNAMICS; PITOT TUBES; PRESSURE MEASUREMENT; PNEUMATIC PROBES
20090040698 NASA Glenn Research Center, Cleveland, OH, United States
Abrasion of Candidate Spacesuit Fabrics by Simulated Lunar Dust
Gaier, James R.; Meador, Mary Ann; Rogers, Kerry J.; Sheehy, Brennan H.; October 2009; In English; 39th International Conference on Environmental Systems (ICES), 12-16 Jul. 2009, Savannah, GA, United States; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 936374.04.08.03
Report No.(s): NASA/TM-2009-215800; 2009-01-2473; E-16958-1; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090040698
A protocol has been developed that produced the type of lunar soil abrasion damage observed on Apollo spacesuits. This protocol was then applied to four materials (Kevlar (DuPont), Vectran (Kuraray Co., Ltd.), Orthofabric, and Tyvek (DuPont)) that are candidates for advanced spacesuits. Three of the four new candidate fabrics (all but Vectran) were effective at keeping the dust from penetrating to layers beneath. In the cases of Kevlar and Orthofabric this was accomplished by the addition of a silicone layer. In the case of Tyvek, the paper structure was dense enough to block dust transport. The least abrasive damage was suffered by the Tyvek. This was thought to be due in large part to its non-woven paper structure. The woven structures were all abraded where the top of the weave was struck by the abrasive. Of these, the Orthofabric suffered the least wear, with both Vectran and Kevlar suffering considerably more extensive filament breakage.
Author
ABRASIVES; FABRICS; KEVLAR (TRADEMARK); LUNAR DUST; SPACE SUITS; LUNAR SOIL; ABRASION
20090040706 NASA Glenn Research Center, Cleveland, OH, United States
Compilation of Trade Studies for the Constellation Program Extravehicular Activity Spacesuit Power System
Fincannon, James; November 2009; In English; Original contains color illustrations
Contract(s)/Grant(s): WBS 731384.06.04.01.31.06.50
Report No.(s): NASA/TM-2009-215803; E-17066; No Copyright; Avail.: CASI: A05, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090040706
This compilation of trade studies performed from 2005 to 2006 addressed a number of power system design issues for the Constellation Program Extravehicular Activity Spacesuit. Spacesuits were required for spacewalks and in-space activities as well as lunar and Mars surface operations. The trades documented here considered whether solar power was feasible for spacesuits, whether spacesuit power generation should be a distributed or a centralized function, whether self-powered in-space spacesuits were better than umbilically powered ones, and whether the suit power system should be recharged in place or replaced.
Author
EXTRAVEHICULAR ACTIVITY; LUNAR SURFACE; SYSTEMS ENGINEERING; SPACE SUITS; CONSTELLATION PROGRAM
Additions to the NASA Aeronautics and Space Database as of 12/18/2009
20090041359 NASA Glenn Research Center, Cleveland, OH, United States
Modeling of Melt-Infiltrated SiC/SiC Composite Properties
Mital, Subodh K.; Bednarcyk, Brett A.; Arnold, Steven M.; Lang, Jerry; October 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 599489.02.07.03.02.02.02
Report No.(s): NASA/TM-2009-215806; E-17069; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090041359
The elastic properties of a two-dimensional five-harness melt-infiltrated silicon carbide fiber reinforced silicon carbide matrix (MI SiC/SiC) ceramic matrix composite (CMC) were predicted using several methods. Methods used in this analysis are multiscale laminate analysis, micromechanics-based woven composite analysis, a hybrid woven composite analysis, and two- and three-dimensional finite element analyses. The elastic properties predicted are in good agreement with each other as well as with the available measured data. However, the various methods differ from each other in three key areas: (1) the fidelity provided, (2) the efforts required for input data preparation, and (3) the computational resources required. Results also indicate that efficient methods are also able to provide a reasonable estimate of local stress fields.
Author
CERAMIC MATRIX COMPOSITES; WOVEN COMPOSITES; FINITE ELEMENT METHOD; MICROMECHANICS; ELASTIC PROPERTIES; FIBER COMPOSITES; HYBRID COMPOSITES
20090041556 NASA Glenn Research Center, Cleveland, OH, United States
Design and Testing of Braided Composite Fan Case Materials and Components
Roberts, Gary D.; Pereira, J. Michael; Braley, Michael S.; Arnold, William a.; Dorer, James D.; Watson, William R/.; October 2009; In English; 19th ISABE Conference (ISABE 2009), 7-11 Sep. 2009, Montreal, Ontario, Canada; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 698259.02.07.03.04.01
Report No.(s): NASA/TM-2009-215811; ISABE-2009-1201; E-17015-1; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090041556
Triaxial braid composite materials are beginning to be used in fan cases for commercial gas turbine engines. The primary benefit for the use of composite materials is reduced weight and the associated reduction in fuel consumption. However, there are also cost benefits in some applications. This paper presents a description of the braided composite materials and discusses aspects of the braiding process that can be utilized for efficient fabrication of composite cases. The paper also presents an approach that was developed for evaluating the braided composite materials and composite fan cases in a ballistic impact laboratory. Impact of composite panels with a soft projectile is used for materials evaluation. Impact of composite fan cases with fan blades or blade-like projectiles is used to evaluate containment capability. A post-impact structural load test is used to evaluate the capability of the impacted fan case to survive dynamic loads during engine spool down. Validation of these new test methods is demonstrated by comparison with results of engine blade-out tests.
Author
BRAIDED COMPOSITES; CONTAINMENT; TERMINAL BALLISTICS; COMPOSITE MATERIALS; COMPOSITE STRUCTURES; FAN BLADES; GAS TURBINE ENGINES; IMPACT LOADS
20090041557 NASA Glenn Research Center, Cleveland, OH, United States
Multiscale Failure Analysis of Laminated Composite Panels Subjected to Blast Loading Using FEAMAC/Explicit
Pineda, Evan J.; Waas, Anthony M.; Berdnarcyk, Brett A.; Arnold, Steven M.; Collier, Craig S.; October 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): NNL07AA29CWBS 984754.02.07.03.16.05
Report No.(s): NASA/TM-2009-215813; E-17075; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090041557
This preliminary report demonstrates the capabilities of the recently developed software implementation that links the Generalized Method of Cells to explicit finite element analysis by extending a previous development which tied the generalized method of cells to implicit finite elements. The multiscale framework, which uses explicit finite elements at the global-scale and the generalized method of cells at the microscale is detailed. This implementation is suitable for both dynamic mechanics problems and static problems exhibiting drastic and sudden changes in material properties, which often encounter convergence issues with commercial implicit solvers. Progressive failure analysis of stiffened and un-stiffened fiber-reinforced laminates subjected to normal blast pressure loads was performed and is used to demonstrate the capabilities of this framework. The focus of this report is to document the development of the software implementation; thus, no comparison between the results of the models and experimental data is drawn. However, the validity of the results are assessed qualitatively through the observation of failure paths, stress contours, and the distribution of system energies.
Author
FINITE ELEMENT METHOD; FAILURE ANALYSIS; FIBER COMPOSITES; PRESSURE DISTRIBUTION; BLAST LOADS; COMPOSITE STRUCTURES
20090041558 NASA Glenn Research Center, Cleveland, OH, United States
Noise-Source Separation Using Internal and Far-Field Sensors for a Full-Scale Turbofan Engine
Hultgren, Lennart S.; Miles, Jeffrey H.; November 2009; In English; 15th Aeroacoustics Conference (30th AIAA Aeroacoustics Conference), 11-13 May 2009, Miami, FL, United States; Original contains color illustrations
Contract(s)/Grant(s): WBS 561581.02.08.03.18.02
Report No.(s): NASA/TM-2009-215834; AIAA-Paper-2009-3220; E-17096; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090041558
Noise-source separation techniques for the extraction of the sub-dominant combustion noise from the total noise signatures obtained in static-engine tests are described. Three methods are applied to data from a static, full-scale engine test. Both 1/3-octave and narrow-band results are discussed. The results are used to assess the combustion-noise prediction capability of the Aircraft Noise Prediction Program (ANOPP). A new additional phase-angle-based discriminator for the three-signal method is also introduced.
Author
NOISE MEASUREMENT; ENGINE NOISE; TURBOFAN ENGINES; COMBUSTION; ENGINE TESTS; FULL SCALE TESTS; NOISE GENERATORS
Additions to the NASA Aeronautics and Space Database as of 12/21/2009
20090041618 NASA Glenn Research Center, Cleveland, OH, United States
Pre-Flight Characterization of Samples for the MISSE-7 Spacesuit Fabric Exposure Experiment
Gaier, James R.; McCue, Terry R.; Clark, Gregory W.; Rogers, Kerry J.; Mengesu, Tsega; October 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 936374.04.08.03
Report No.(s): NASA/TM-2009-215810; E-17073; Copyright; Avail.: CASI: A05, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090041618
A series of six sample spacesuit pressure garment assembly (PGA) fabric samples were prepared for the Materials International Space Station Experiment 7 (MISSE-7) flight experiment to test the effects of damage by lunar dust on the susceptibility of the fabrics to radiation damage. These included pristine Apollo-era fluorinated ethylene-propylene (FEP) fabric, Apollo-era FEP fabric that had been abraded with JSC-1A lunar simulant, and a piece of Alan Bean s Apollo 12 PGA sectioned from near the left knee. Also included was a sample of pristine orthofabric, and orthofabric that had been abraded to two different levels with JSC-1A. The samples were characterized using optical microscopy, field emission scanning electron microscopy, and atomic force microscopy. Two sets of six samples were then loaded in space environment exposure hardware, one of which was stored as control samples. The other set was affixed to the MISSE-7 experiment package, and will be mounted on the International Space Station, and exposed to the wake-side low Earth orbit environment. It will be retrieved after an exposure of approximately 12 months, and returned for post flight analysis.
Author
LUNAR DUST; GARMENTS; SPACE SUITS; FABRICS; AEROSPACE ENVIRONMENTS; POSTFLIGHT ANALYSIS; RADIATION DAMAGE; SCANNING ELECTRON MICROSCOPY
Additions to the NASA Aeronautics and Space Database as of 12/22/2009
20090041726 NASA Glenn Research Center, Cleveland, OH, United States
2008 NASA Seal/Secondary Air System Workshop
Steinetz, Bruce M., Editor; Hendricks, Robert C., Editor; Delgado, Irebert R., Editor; November 2009; In English; 2008 NASA Seal/Secondary Air System Workshop, 18 Nov. 2008, Cleveland, OH, United States; Original contains color illustrations
Contract(s)/Grant(s): WBS 092837.04.01.04.04.03
Report No.(s): NASA/CP-2009-215677; E-17043; Copyright; Avail.: CASI: A13, Hardcopy: C01, CD-ROM
Avail Online: http://hdl.handle.net/2060/20090041726
The 2008 NASA Seal/Secondary Air System Workshop covered the following topics: (i) Overview of NASA s new Orion project aimed at developing a new spacecraft that will fare astronauts to the International Space Station, the Moon, Mars, and beyond; (ii) Overview of NASA s fundamental aeronautics technology project; (iii) Overview of NASA Glenn s seal project aimed at developing advanced seals for NASA s turbomachinery, space, and reentry vehicle needs; (iv) Reviews of NASA prime contractor, vendor, and university advanced sealing concepts, test results, experimental facilities, and numerical predictions; and (v) Reviews of material development programs relevant to advanced seals development. Turbine engine studies have shown that reducing seal leakage as well as high-pressure turbine (HPT) blade tip clearances will reduce fuel burn, lower emissions, retain exhaust gas temperature margin, and increase range. Turbine seal development topics covered include a method for fast-acting HPT blade tip clearance control, noncontacting low-leakage seals, intershaft seals, and a review of engine seal performance requirements for current and future Army engine platforms.
Author
SEALING; AERONAUTICAL ENGINEERING; EXHAUST GASES; TURBINE ENGINES; TURBOMACHINERY; NUMERICAL ANALYSIS; GAS TEMPERATURE; HIGH PRESSURE; THERMAL BARRIERS (PLASMA CONTROL)
20090041727 NASA Glenn Research Center, Cleveland, OH, United States
Overview of CEV Thermal Protection System Seal Development
DeMange, Jeff; Taylor, Shawn; Dunlap, Patrick; Steinetz, Bruce; Delgado, Irebert; Finkbeiner, Josh; Mayer, John; 2008 NASA Seal/Secondary Air System Workshop; November 2009; pp. 253-26; In English; Original contains color illustrations
Copyright; Avail.: CASI: A03, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document
Avail Online: http://hdl.handle.net/2060/20090041727
NASA GRC supporting design, development, and implementation of numerous seal systems for the Orion CEV: a) HS-to-BS interface. b) Compression pad. HS-to-BS Interface Seal System: a) design has evolved as a result of changes with the CEV TPS. b) Seal system is currently under development/evaluation. Coupon level tests, Arc jet tests, and Validation test development. Compression Pad: a) Finalizing design options. b) Evaluating material candidates.
Author
DESIGN ANALYSIS; SYSTEMS ENGINEERING; THERMAL PROTECTION; SEALS (STOPPERS)
20090041728 Parker-Hannifin Corp., North Haven, CT, United States
Ultra-High Temperature Metallic Seal/Energizer Development for Aero Propulsion and Gas Turbine Applications
Cornett, Ken; Newman, Jesse; Datta, Amit; 2008 NASA Seal/Secondary Air System Workshop; November 2009; pp. 271-28; In English; Original contains color illustrations
Copyright; Avail.: CASI: A03, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document
Avail Online: http://hdl.handle.net/2060/20090041728
The industry is requiring seals to operate at higher and higher temperatures. Traditional static seal designs and materials experience stress relaxation, losing their ability to maintain contact with moving flanges. Ultra High Temperature seal development program is a multiphase program with incremental increases in seal operating temperatures.
Author
SEALS (STOPPERS); HIGH TEMPERATURE; OPERATING TEMPERATURE; FLANGES; AIRCRAFT ENGINES; GAS TURBINE ENGINES
20090041729 NASA, Washington, DC, United States
Fundamental Aeronautics Program
Misra, Ajay; 2008 NASA Seal/Secondary Air System Workshop; November 2009; pp. 25-5; In English; Original contains color illustrations
Copyright; Avail.: CASI: A03, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document
Avail Online: http://hdl.handle.net/2060/20090041729
The Overarching Mission of NASA's Aeronautics Research Mission Directorate (ARMD) is: To advance U.S. technological leadership in aeronautics in partnership with industry, academia, and other government agencies that conduct aeronautics-related research. ARMD supports the Agency's goal of developing a balanced overall program of science, exploration, and aeronautics, and ARMD's research plans also directly support the National Aeronautics R&D Policy and accompanying Executive Order 131419.
Author
AERONAUTICS; RESEARCH AND DEVELOPMENT; LEADERSHIP; RESEARCH MANAGEMENT
20090041730 Rolls-Royce Corp., Indianapolis, IN, United States
Foil Face Seal Testing
Munson, John; 2008 NASA Seal/Secondary Air System Workshop; November 2009; pp. 131-13; In English; Original contains color illustrations
Copyright; Avail.: CASI: A02, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document
Avail Online: http://hdl.handle.net/2060/20090041730
In the seal literature you can find many attempts by various researchers to adapt film riding seals to the gas turbine engine. None have been successful, potential distortion of the sealing faces is the primary reason. There is a film riding device that does accommodate distortion and is in service in aircraft applications, namely the foil bearing. More specifically a foil thrust bearing. These are not intended to be seals, and they do not accommodate large axial movement between shaft & static structure. By combining the 2 a unique type of face seal has been created. It functions like a normal face seal. The foil thrust bearing replaces the normal primary sealing surface. The compliance of the foil bearing allows the foils to track distortion of the mating seal ring. The foil seal has several perceived advantages over existing hydrodynamic designs, enumerated in the chart. Materials and design methodology needed for this application already exist. Also the load capacity requirements for the foil bearing are low since it only needs to support itself and overcome friction forces at the antirotation keys.
Author
FOIL BEARINGS; SEALING; SEALS (STOPPERS); THRUST BEARINGS; LOADS (FORCES); FRICTION; SHAFTS (MACHINE ELEMENTS)
20090041731 NASA Glenn Research Center, Cleveland, OH, United States
Overview of NASA Glenn Seal Project
Steinetz, Bruce M.; Dunlap, Patrick H., Jr.; Proctor, Margaret; Delgado, Irebert; Finkbeiner,Joshua; deGroh, Henry; Ritzert, Frank; Daniels, Christopher; DeMange, Jeff; Taylor, Shawn; Wasowski, Janice; Smith, Ian; Penney, Nicholas; Garafolo, Nicholas; 2008 NASA Seal/Secondary Air System Workshop; November 2009; pp. 57-9; In English; Original contains color and black and white illustrations
Copyright; Avail.: CASI: A03, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document
Avail Online: http://hdl.handle.net/2060/20090041731
NASA Glenn is currently performing seal research supporting both advanced turbine engine development and advanced space vehicle/propulsion system development. Studies have shown that decreasing parasitic leakage by applying advanced seals will increase turbine engine performance and decrease operating costs. Studies have also shown that higher temperature, long life seals are critical in meeting next generation space vehicle and propulsion system goals in the areas of performance, reusability, safety, and cost. Advanced docking system seals need to be very robust resisting space environmental effects while exhibiting very low leakage and low compression and adhesion forces. NASA Glenn is developing seal technology and providing technical consultation for the Agencys key aero- and space technology development programs.
Author
SEALS (STOPPERS); AEROSPACE ENGINEERING; TURBINE ENGINES; SYSTEMS ENGINEERING; SEALING; LEAKAGE; AEROSPACE ENVIRONMENTS; ENGINE DESIGN
20090041732 GE Global Research Center, Niskayuna, NY, United States
An Overview of Non-Metallic Brush Seal Technology
Ruggiero, Eric J.; 2008 NASA Seal/Secondary Air System Workshop; November 2009; pp. 193-20; In English; Original contains color and black and white illustrations
Copyright; Avail.: CASI: A03, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document
Avail Online: http://hdl.handle.net/2060/20090041732
Non-metallic brush seals are ultra-low flow sealing elements ideal for low pressure differentials (<30 psid) and low temperature (typically <300 degF) applications. The compliant bristle pack of a non-metallic brush seal is advantageous in terms of sealing capability during transients. However, if not designed properly, the bristle pack compliance can be detrimental to the performance of the seal. GE GLobal Research has investigated the stiffness and heat generation properties of non-metallic brush seals made from Kevlar and Carbon Fiber. The presentation will review the progress made on the design points of the seals, as well as highlight some current commercial applications of the technology.
Author
SEALING; BRUSH SEALS; ELASTIC PROPERTIES; CARBON FIBERS; HEAT GENERATION; KEVLAR (TRADEMARK)
20090041733 NASA Glenn Research Center, Cleveland, OH, United States
Preliminary Test Results of a Non-Contacting Finger Seal on a Herringbone-Grooved Rotor
Proctor, Margaret P.; Delgado, Irebert R.; 2008 NASA Seal/Secondary Air System Workshop; November 2009; pp. 139-15; In English; Original contains color and black and white illustrations
Copyright; Avail.: CASI: A03, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document
Avail Online: http://hdl.handle.net/2060/20090041733
The baseline non-contacting finger seal is a NASA patented design. The primary difference between it and Gul Aroras design patented by AlliedSignal is that there are no lift pads on the high pressure fingers. The baseline non-contacting finger seal is comprised of a back plate, aft spacer, aft (or low pressure) finger element, forward (or high pressure) finger element, forward spacer, and front plate. The components are held together with 20 flat head screws. A typical seal would have a back plate of approximately the same thickness as the front plate and would be riveted together. The thicker back plate allows use of threaded fasteners so that different finger elements can be tested without having to replace all the individual seal components. The finger elements are essentially washers made of thin sheet stock with multiple curved slots machined around the inner diameter to form the fingers. They are clocked so that the fingers of one cover the slots of the other. The aft finger element fingers have axial extensions or "lift pads" at the seal id that are concentric to the rotor. The fingers act as cantilever beams and flex in response to rotor dynamic motion and radial growth of the rotor due to centrifugal or thermal forces.
Author
SEALS (STOPPERS); CANTILEVER BEAMS; ROTOR DYNAMICS; ROTORS; CENTRIFUGAL FORCE; FASTENERS
20090041734 NASA Glenn Research Center, Cleveland, OH, United States
NASA's Constellation Program
Baumeister, Joseph; 2008 NASA Seal/Secondary Air System Workshop; November 2009; pp. 1-2; In English; Original contains color illustrations
Copyright; Avail.: CASI: A03, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document
Avail Online: http://hdl.handle.net/2060/20090041734
NASA has established 6 Themes for Exploration: 1) USE THE MOON: Reduce risks and cost and increase productivity of future missions by testing technologies, systems, and operations in a planetary environment other than the Earth. 2) PURSUE SCIENTIFIC: Engage in scientific investigations of the Moon (solar system processes), on the Moon (use the unique environment), and from the Moon (to study other celestial phenomena). 3) EXTEND PERMANENT HUMAN PRESENCE: Develop the capabilities and infrastructure required to expand the number of people, the duration, the self-sufficiency, and the degree of non-governmental activity. 4) EXPAND EARTH S ECONOMIC SPHERE: Create new markets based on lunar activity that will return economic, technological, and quality-of-life benefits. 5) ENHANCE GLOBAL SECURTIY: Provide a challenging, shared, and peaceful global vision that unites nations in pursuit of common objectives. 6) ENGAGE, INSPIRE: Excite the public about space, encourage students to pursue careers in high technology fields, ensure that individuals enter the workforce with the scientific and technical knowledge necessary to sustain exploration.
Author
CONSTELLATION PROGRAM; PLANETARY ENVIRONMENTS; SOLAR SYSTEM; MARKET RESEARCH; MOON
20090041735 NASA Glenn Research Center, Cleveland, OH, United States
Synthetic and Biomass Alternate Fueling in Aviation
Hendricks, Robert C.; Bushnell, Dennis M.; 2008 NASA Seal/Secondary Air System Workshop; November 2009; pp. 91-13; In English; Original contains color illustrations
Copyright; Avail.: CASI: A03, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document
Avail Online: http://hdl.handle.net/2060/20090041735
Must use earth's most abundant natural resources - Biomass, Solar, Arid land (43%), Seawater (97%) with nutrients (80%) plus brackish waters and nutrients resolve environmental triangle of conflicts energy-food-freshwater and ultrafine particulate hazards. Requires Paradigm Shift - Develop and Use Solar* for energy; Biomass for aviation and hybrid-electric-compressed air mobility fueling with transition to hydrogen long term.
Author
BIOMASS; WATER RESOURCES; EARTH RESOURCES; REFUELING; COMPRESSED AIR; HAZARDS; HYDROGEN
20090041736 Timken Co., Canton, OH, United States
Low-Torque Seal Development
Lattime, Scott B.; Borowski, Richard; 2008 NASA Seal/Secondary Air System Workshop; November 2009; pp. 159-19; In English; Original contains color and black and white illustrations
Copyright; Avail.: CASI: A03, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document
Avail Online: http://hdl.handle.net/2060/20090041736
The EcoTurn Class K production prototypes have passed all AAR qualification tests and received conditional approval. The accelerated life test on the second set of seals is in progress. Due to the performance of the first set, no problems are expected.The seal has demonstrated superior performance over the HDL seal in the test lab with virtually zero torque and excellent contamination exclusion and grease retention.
Author
ACCELERATED LIFE TESTS; SEALS (STOPPERS); PERFORMANCE TESTS; TORQUE; EXCLUSION
20090041737 Parker-Hannifin Corp., San Diego, CA, United States
Design and Analysis of Molded Elastomer Seals
Yetter, Paul; Zhang, Kai; 2008 NASA Seal/Secondary Air System Workshop; November 2009; pp. 233-25; In English; Original contains color illustrations
Copyright; Avail.: CASI: A03, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document
Avail Online: http://hdl.handle.net/2060/20090041737
Modeling Materials: a) Hyperelastic model used for room temperature and higher, but has limitations at predicting response at different compressive rates and at low temperatures. b) Viscoelastic model is rarely used, and needs more research and application. Test and Characterization of Materials: a) Better material characterization using biaxial tension vs simple compression testing modes is debatable. b) Testing at high and low temperature is challenging.
Author
LOW TEMPERATURE; HIGH TEMPERATURE; ELASTOMERS; VISCOELASTICITY; ROOM TEMPERATURE; COMPRESSIBILITY; DESIGN ANALYSIS; SEALING
20090041738 General Electric Energy, Greenville, SC, United States
Update on DOE Advanced IGCC/H2 Gas Turbine
Chupp, Ray; 2008 NASA Seal/Secondary Air System Workshop; November 2009; pp. 207-22; In English; Original contains color illustrations
Contract(s)/Grant(s): DE-FC26-05NT42643
Copyright; Avail.: CASI: A03, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document
Avail Online: http://hdl.handle.net/2060/20090041738
Cooling Flow Reduction: a) Focus on improving turbine hot gas path part cooling efficiency. b) Applicable to current metallic turbine components and synergistic with advanced materials. c) Address challenges of IGCC/hydrogen fuel environment (for example, possible cooling hole plugging). Leakage Flow Reduction: a) Focus on decreasing turbine parasitic leakages, i.e. between static-to-static, static-to-rotating turbine parts. b) Develop improved seal designs in a variety of important areas. Purge Flow Reduction: a) Focus on decreasing required flows to keep rotor disk cavities within temperature limits. b) Develop improved sealing at the cavity rims and modified flow geometries to minimize hot gas ingestion and aerodynamic impact.
Author
HEAT TRANSFER; TURBINES; HIGH TEMPERATURE GASES; GAS PATH ANALYSIS; CAVITY FLOW; SEALING; FLOW GEOMETRY; GAS COOLING; HYDROGEN FUELS
20090041739 NASA Glenn Research Center, Cleveland, OH, United States
Overview of LIDS Docking Seals Development
Dunlap, Patrick; Steinetz, Bruce; Daniels, Christopher; 2008 NASA Seal/Secondary Air System Workshop; November 2009; pp. 223-23; In English; Original contains color illustrations
Copyright; Avail.: CASI: A02, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document
Avail Online: http://hdl.handle.net/2060/20090041739
GRC is supporting JSC by developing LIDS main interface seals Seal development and testing is occurring at both sub-scale and full-scale levels: a) Small-scale tests performed to define seal materials and evaluate exposure to space environments. b) Medium-scale testing: 1) Permits evaluation of candidate seal designs at faster pace than for full-scale seals. 2) Leak rates and loads can be scaled up to full-scale for indication of seal performance. c) Full-scale test rigs used for seal development and flight qualification tests and to assess on-orbit anomalies if needed. GRC responsible for delivering flight hardware seals to JSC approx.2013 for integration into LIDS flight units.
Author
SEALS (STOPPERS); AEROSPACE ENVIRONMENTS; PERFORMANCE TESTS; LOADS (FORCES); FULL SCALE TESTS
20090041828 NASA Langley Research Center, Hampton, VA, United States
A Multidisciplinary Tool for Systems Analysis of Planetary Entry, Descent, and Landing (SAPE)
Samareah, Jamshid A.; November 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 346620.04.07.01.01.02
Report No.(s): NASA/TM-2009-215950; L-19730; LF99-9217; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090041828
SAPE is a Python-based multidisciplinary analysis tool for systems analysis of planetary entry, descent, and landing (EDL) for Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Titan. The purpose of SAPE is to provide a variable-fidelity capability for conceptual and preliminary analysis within the same framework. SAPE includes the following analysis modules: geometry, trajectory, aerodynamics, aerothermal, thermal protection system, and structural sizing. SAPE uses the Python language-a platform-independent open-source software for integration and for the user interface. The development has relied heavily on the object-oriented programming capabilities that are available in Python. Modules are provided to interface with commercial and government off-the-shelf software components (e.g., thermal protection systems and finite-element analysis). SAPE runs on Microsoft Windows and Apple Mac OS X and has been partially tested on Linux.
Author
SYSTEMS ANALYSIS; ATMOSPHERIC ENTRY; DESCENT; LANDING; SYSTEMS INTEGRATION; LANGUAGE PROGRAMMING; MULTIDISCIPLINARY DESIGN OPTIMIZATION
20090041834 NASA Glenn Research Center, Cleveland, OH, United States
Broadband Shock Noise in Internally-Mixed Dual-Stream Jets
Bridges, James E.; November 2009; In English; 15th Aeroacoustics Conference (30th AIAA Aeroacoustics Conference), 11-13 May 2009, Miami, FL, United States
Contract(s)/Grant(s): WBS 984754.02.07.03.17.03
Report No.(s): NASA/TM-2009-215817; AIAA-Paper-2009-3210; E-17079; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090041834
Broadband shock noise (BBSN) has been studied in some detail in single-flow jets and recently in dual-stream jets with separate flow exhaust systems. Shock noise is of great concern in these latter cases because of the noise created for the aircraft cabin by the underexpanded nozzle flow at cruise. Another case where shock noise is of concern is in the case of future supersonic aircraft that are expected to have bypass ratios small enough to justify internally mixed exhaust systems, and whose mission will push cycles to the point of imperfectly expanded flows. Dual-stream jets with internally mixed plume have some simplifying aspects relative to the separate flow jets, having a single shock structure given by the common nozzle pressure. This is used to separate the contribution of the turbulent shear layer to the broadband shock noise. Shock structure is held constant while the geometry and strength of the inner and merged shear layers are varying by changing splitter area ratio and core stream temperature. Flow and noise measurements are presented which document the efforts at separating the contribution of the inner shear layer to the broadband shock noise.
Author
AERODYNAMIC NOISE; NOZZLE FLOW; NOISE MEASUREMENT; FLOW NOISE; SHOCK WAVES; BYPASS RATIO; SHEAR LAYERS
Additions to the NASA Aeronautics and Space Database as of 12/25/2009
20090042496 NASA Langley Research Center, Hampton, VA, United States
Operational Improvements From Using the In-Trail Procedure in the North Atlantic Organized Track System
Chartrand, Ryan C.; Bussink, Frank J.; Graff, Thomas J.; Jones, Kenneth M.; October 2009; In English; Original contains color and black and white illustrations
Report No.(s): NASA/TM-2009-215939; L-19466; LF99-6894; Copyright; Avail.: CASI: A04, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042496
This paper explains the computerized batch processing experiment examining the operational impacts of the introduction of Automatic Dependent Surveillance-Broadcast (ADS-B) equipment and the In-Trail Procedure (ITP) to the North Atlantic Organized Track System. This experiment was conducted using the Traffic Manager (TMX), a desktop simulation capable of simulating airspace environments and aircraft operations. ADS-B equipment can enable the use of new ground and airborne procedures, such as the ITP. ITP is among the first of these new procedures, which will make use of improved situation awareness in the local surrounding airspace of ADS-B equipped aircraft to enable more efficient oceanic flight level changes. The collected data were analyzed with respect to multiple operationally relevant parameters including fuel burn, request approval rates, and the distribution of fuel savings. This experiment showed that through the use of ADS-B or ADS-B and the ITP that operational improvements and benefits could be achieved.
Author
SURVEILLANCE; ENVIRONMENT SIMULATION; BROADCASTING; AIRSPACE; MIRROR FUSION
20090042511 NASA Langley Research Center, Hampton, VA, United States
Exploring a Method for Improving Turbulent Separated-Flow Predictions with kappa-omega Models
Rumsey, Christopher L.; December 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 561581.02.08.07.20.15
Report No.(s): NASA/TM-2009-215952; L-19779; LF99-9618; No Copyright; Avail.: CASI: A04, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042511
A particular failing of Reynolds-averaged Navier-Stokes separated turbulent flow computations is addressed within the context of a kappa-omega two-equation turbulence model. The failing is the tendency for turbulence models to under-predict turbulent shear stress in the shear layers of some separation bubbles, yielding late boundary layer reattachment and recovery. Inspired by unpublished work of Volker, Langtry, and Menter, the author undertook an independent investigation in an attempt to improve the ability of the Menter shear stress transport (SST) model to predict flowfield characteristics in and downstream of separation bubbles. The fix is an ad hoc term that is a function of the local ratio of turbulent production to dissipation; it is used to multiply the omega-destruction term, increasing eddy viscosity in separated regions. With this fix, several flowfields are investigated. Results show that, although the "separation fix" can provide dramatic improvement in some cases, it is not consistently good for all flows. Thus, although it may prove helpful in many situations in its current form, this model may benefit from further refinements, including better sensitization to the energetics of turbulence in the separated region.
Author
COMPUTATIONAL FLUID DYNAMICS; EDDY VISCOSITY; TURBULENCE MODELS; SEPARATED FLOW; BOUNDARY LAYERS; FLOW DISTRIBUTION; NAVIER-STOKES EQUATION; REYNOLDS AVERAGING; SHEAR STRESS; TURBULENT FLOW
20090042518 NASA Langley Research Center, Hampton, VA, United States
Metrics for the NASA Airspace Systems Program
Smith, Jeremy C.; Neitzke, Kurt W.; December 2009; In English; Original contains color illustrations
Contract(s)/Grant(s): WBS 411931.02.71.07.01
Report No.(s): NASA/SP-2009-6115; LF99-9261; L-19732; No Copyright; Avail.: CASI: A04, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042518
This document defines an initial set of metrics for use by the NASA Airspace Systems Program (ASP). ASP consists of the NextGen-Airspace Project and the NextGen-Airportal Project. The work in each project is organized along multiple, discipline-level Research Focus Areas (RFAs). Each RFA is developing future concept elements in support of the Next Generation Air Transportation System (NextGen), as defined by the Joint Planning and Development Office (JPDO). In addition, a single, system-level RFA is responsible for integrating concept elements across RFAs in both projects and for assessing system-wide benefits. The primary purpose of this document is to define a common set of metrics for measuring National Airspace System (NAS) performance before and after the introduction of ASP-developed concepts for NextGen as the system handles increasing traffic. The metrics are directly traceable to NextGen goals and objectives as defined by the JPDO and hence will be used to measure the progress of ASP research toward reaching those goals. The scope of this document is focused on defining a common set of metrics for measuring NAS capacity, efficiency, robustness, and safety at the system-level and at the RFA-level. Use of common metrics will focus ASP research toward achieving system-level performance goals and objectives and enable the discipline-level RFAs to evaluate the impact of their concepts at the system level.
Author
AIRSPACE; NATIONAL AIRSPACE SYSTEM; NASA PROGRAMS; AIR TRANSPORTATION; MANAGEMENT PLANNING
20090042519 NASA Langley Research Center, Hampton, VA, United States
An Amplitude-Based Estimation Method for International Space Station (ISS) Leak Detection and Localization Using Acoustic Sensor Networks
Tian, Jialin; Madaras, Eric I.; November 2009; In English; Original contains color illustrations
Contract(s)/Grant(s): WBS 401769.06.03.01.02.12
Report No.(s): NASA/TM-2009-215948; LF99-9595; L-19789; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042519
The development of a robust and efficient leak detection and localization system within a space station environment presents a unique challenge. A plausible approach includes the implementation of an acoustic sensor network system that can successfully detect the presence of a leak and determine the location of the leak source. Traditional acoustic detection and localization schemes rely on the phase and amplitude information collected by the sensor array system. Furthermore, the acoustic source signals are assumed to be airborne and far-field. Likewise, there are similar applications in sonar. In solids, there are specialized methods for locating events that are used in geology and in acoustic emission testing that involve sensor arrays and depend on a discernable phase front to the received signal. These methods are ineffective if applied to a sensor detection system within the space station environment. In the case of acoustic signal location, there are significant baffling and structural impediments to the sound path and the source could be in the near-field of a sensor in this particular setting.
Author
SIGNAL DETECTORS; SOUND DETECTING AND RANGING; LEAKAGE; ACOUSTIC EMISSION; INTERNATIONAL SPACE STATION; SIGNAL TRANSMISSION; SOUND GENERATORS; SOUND WAVES
20090042555 Southwest Research Inst., San Antonio, TX, United States; ATK Space Systems, Inc., Beltsville, MD, United States
Model for the Effect of Fiber Bridging on the Fracture Resistance of Reinforced-Carbon-Carbon
Chan, Kwai S.; Lee, Yi-Der; Hudak, Stephen J., Jr.; November 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): NNL07AA00BWBS 869021.05.07.04.99
Report No.(s): NASA/CR-2009-215947; LF99-9886; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042555
A micromechanical methodology has been developed for analyzing fiber bridging and resistance-curve behavior in reinforced-carbon-carbon (RCC) panels with a three-dimensional (3D) composite architecture and a silicon carbide (SiC) surface coating. The methodology involves treating fiber bridging traction on the crack surfaces in terms of a weight function approach and a bridging law that relates the bridging stress to the crack opening displacement. A procedure has been developed to deduce material constants in the bridging law from the linear portion of the K-resistance curve. This report contains information on the application of procedures and outcomes.
Author
SURFACE CRACKS; CARBON; FRACTURE STRENGTH; CRACK OPENING DISPLACEMENT; THREE DIMENSIONAL COMPOSITES; SILICON CARBIDES; CRACK BRIDGING; MICROMECHANICS
Additions to the NASA Aeronautics and Space Database as of 12/30/2009
20090042723 NASA Glenn Research Center, Cleveland, OH, United States
Development of Jet Noise Power Spectral Laws Using SHJAR Data
Khavaran, Abbas; Bridges, James; October 2009; In English; FROM 30th AIAA Aeroacoustics Conference, 11-13 May 2009, Miami, FL, United States; Original contains color and black and white illustrations
Contract(s)/Grant(s): NNC06BA07BWBS 561581.02.08.03.18.02
Report No.(s): NASA/TM-2009-215674; AIAA Paper 2009-3378; E-17036; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042723
High quality jet noise spectral data measured at the Aeroacoustic Propulsion Laboratory at the NASA Glenn Research Center is used to examine a number of jet noise scaling laws. Configurations considered in the present study consist of convergent and convergent-divergent axisymmetric nozzles. Following the work of Viswanathan, velocity power factors are estimated using a least squares fit on spectral power density as a function of jet temperature and observer angle. The regression parameters are scrutinized for their uncertainty within the desired confidence margins. As an immediate application of the velocity power laws, spectral density in supersonic jets are decomposed into their respective components attributed to the jet mixing noise and broadband shock associated noise. Subsequent application of the least squares method on the shock power intensity shows that the latter also scales with some power of the shock parameter. A modified shock parameter is defined in order to reduce the dependency of the regression factors on the nozzle design point within the uncertainty margins of the least squares method.
Author
JET AIRCRAFT NOISE; AERODYNAMIC NOISE; AEROACOUSTICS; JET MIXING FLOW; NOZZLE DESIGN; CONVERGENT NOZZLES; EMISSION SPECTRA
20090042733 NASA Glenn Research Center, Cleveland, OH, United States
Probabilistic Estimation of Critical Flaw Sizes in the Primary Structure Welds of the Ares I-X Launch Vehicle
Pai, Shantaram S.; Hoge, Peter A.; Patel, B. M.; Nagpal, Vinod K.; November 2009; In English; ASME Turbo Expo 2008 Conference, 9-13 Jun. 2008, Berlin, Germany; Original contains color illustrations
Contract(s)/Grant(s): WBS 136905.0.10.80.20.40.01
Report No.(s): NASA/TM-2009-215583; GT2008-50626; E-16824; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042733
The primary structure of the Ares I-X Upper Stage Simulator (USS) launch vehicle is constructed of welded mild steel plates. There is some concern over the possibility of structural failure due to welding flaws. It was considered critical to quantify the impact of uncertainties in residual stress, material porosity, applied loads, and material and crack growth properties on the reliability of the welds during its pre-flight and flight. A criterion--an existing maximum size crack at the weld toe must be smaller than the maximum allowable flaw size--was established to estimate the reliability of the welds. A spectrum of maximum allowable flaw sizes was developed for different possible combinations of all of the above listed variables by performing probabilistic crack growth analyses using the ANSYS finite element analysis code in conjunction with the NASGRO crack growth code. Two alternative methods were used to account for residual stresses: (1) The mean residual stress was assumed to be 41 ksi and a limit was set on the net section flow stress during crack propagation. The critical flaw size was determined by parametrically increasing the initial flaw size and detecting if this limit was exceeded during four complete flight cycles, and (2) The mean residual stress was assumed to be 49.6 ksi (the parent material s yield strength) and the net section flow stress limit was ignored. The critical flaw size was determined by parametrically increasing the initial flaw size and detecting if catastrophic crack growth occurred during four complete flight cycles. Both surface-crack models and through-crack models were utilized to characterize cracks in the weld toe.
Author
LAUNCH VEHICLES; STRUCTURAL FAILURE; WELDED JOINTS; ARES 1 LAUNCH VEHICLE; CRACK PROPAGATION; MECHANICAL PROPERTIES; RESIDUAL STRESS; SURFACE CRACKS; YIELD STRENGTH
20090042749 NASA Glenn Research Center, Cleveland, OH, United States
The Advanced Noise Control Fan Baseline Measurements
McAllister, Joseph; Loew, Raymond A.; Lauer, Joel T.; Stuliff, Daniel L.; October 2009; In English; 47th Aerospace Sciences Meeting, 5-8 Jan. 2009, Orlando, FL, United States; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 561581.02.08.03.18.02
Report No.(s): NASA/TM-2009-215595; AIAA Paper 2009-0624; E-16886; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042749
The NASA Glenn Research Center s (NASA Glenn) Advanced Noise Control Fan (ANCF) was developed in the early 1990s to provide a convenient test bed to measure and understand fan-generated acoustics, duct propagation, and radiation to the farfield. As part of a complete upgrade, current baseline and acoustic measurements were documented. Extensive in-duct, farfield acoustic, and flow field measurements are reported. This is a follow-on paper to documenting the operating description of the ANCF.
Author
NOISE REDUCTION; ACOUSTIC MEASUREMENT; SOUND WAVES; FAR FIELDS
20090042751 NASA Glenn Research Center, Cleveland, OH, United States
Experimental Investigation of the Application of Microramp Flow Control to an Oblique Shock Interaction
Hirt, Stefanie M.; Anderson, Bernhard H.; November 2009; In English; 47th Aerospace Sciences Meeting, 5-8 Jan. 2009, Orlando, FL, United States; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 984754.02.07.03.13.02
Report No.(s): NASA/TM-2009-215630; AIAA Paper 2009-919; E-16942; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042751
The effectiveness of microramp flow control devices in controlling an oblique shock interaction was tested in the 15- by 15-Centimeter Supersonic Wind Tunnel at NASA Glenn Research Center. Fifteen microramp geometries were tested varying the height, chord length, and spacing between ramps. Measurements of the boundary layer properties downstream of the shock reflection were analyzed using design of experiments methods. Results from main effects, D-optimal, full factorial, and central composite designs were compared. The designs provided consistent results for a single variable optimization.
Author
OBLIQUE SHOCK WAVES; BOUNDARY LAYERS; SHOCK WAVE INTERACTION; EXPERIMENT DESIGN; FACTORIAL DESIGN
20090042768 NASA Glenn Research Center, Cleveland, OH, United States
Axial and Centrifugal Compressor Mean Line Flow Analysis Method
Veres, Joseph P.; November 2009; In English; 47th Aerospace Sciences Meeting, 5-8 Jan. 2009, Orlando, FL, United States; Original contains black and white illustrations
Contract(s)/Grant(s): WBS 561581.02.08.03.21.03
Report No.(s): NASA/TM-2009-215585; AIAA Paper 2009-1641; E-16825; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042768
This paper describes a method to estimate key aerodynamic parameters of single and multistage axial and centrifugal compressors. This mean-line compressor code COMDES provides the capability of sizing single and multistage compressors quickly during the conceptual design process. Based on the compressible fluid flow equations and the Euler equation, the code can estimate rotor inlet and exit blade angles when run in the design mode. The design point rotor efficiency and stator losses are inputs to the code, and are modeled at off design. When run in the off-design analysis mode, it can be used to generate performance maps based on simple models for losses due to rotor incidence and inlet guide vane reset angle. The code can provide an improved understanding of basic aerodynamic parameters such as diffusion factor, loading levels and incidence, when matching multistage compressor blade rows at design and at part-speed operation. Rotor loading levels and relative velocity ratio are correlated to the onset of compressor surge. NASA Stage 37 and the three-stage NASA 74-A axial compressors were analyzed and the results compared to test data. The code has been used to generate the performance map for the NASA 76-B three-stage axial compressor featuring variable geometry. The compressor stages were aerodynamically matched at off-design speeds by adjusting the variable inlet guide vane and variable stator geometry angles to control the rotor diffusion factor and incidence angles.
Author
TURBOCOMPRESSORS; FLUID FLOW; COMPUTATIONAL FLUID DYNAMICS; COMPRESSIBLE FLUIDS; DESIGN ANALYSIS; GUIDE VANES; CENTRIFUGAL COMPRESSORS
Additions to the NASA Aeronautics and Space Database as of 12/31/2009
20090042802 NASA Glenn Research Center, Cleveland, OH, United States
Simulating Bone Loss in Microgravity Using Mathematical Formulations of Bone Remodeling
Pennline, James A.; November 2009; In English; Original contains color illustrations
Contract(s)/Grant(s): WBS 516724.02.02.08.01
Report No.(s): NASA/TM-2009-215824; E-17086; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042802
Most mathematical models of bone remodeling are used to simulate a specific bone disease, by disrupting the steady state or balance in the normal remodeling process, and to simulate a therapeutic strategy. In this work, the ability of a mathematical model of bone remodeling to simulate bone loss as a function of time under the conditions of microgravity is investigated. The model is formed by combining a previously developed set of biochemical, cellular dynamics, and mechanical stimulus equations in the literature with two newly proposed equations; one governing the rate of change of the area of cortical bone tissue in a cross section of a cylindrical section of bone and one governing the rate of change of calcium in the bone fluid. The mechanical stimulus comes from a simple model of stress due to a compressive force on a cylindrical section of bone which can be reduced to zero to mimic the effects of skeletal unloading in microgravity. The complete set of equations formed is a system of first order ordinary differential equations. The results of selected simulations are displayed and discussed. Limitations and deficiencies of the model are also discussed as well as suggestions for further research.
Author
BONE DEMINERALIZATION; MATHEMATICAL MODELS; MUSCULOSKELETAL SYSTEM; BIOCHEMISTRY; MICROGRAVITY
20090042816 NASA Glenn Research Center, Cleveland, OH, United States
Impact Testing on Reinforced Carbon-Carbon Flat Panels with Ice Projectiles for the Space Shuttle Return to Flight Program
Melis, Matthew E.; Revilock, Duane M.; Pereira, Michael J.; Lyle, Karen H.; November 2009; In English; Original contains color illustrations
Contract(s)/Grant(s): WBS 377816.06.03.02.04
Report No.(s): NASA/TM-2009-213641; E-15129; No Copyright; Avail.: CASI: A11, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042816
Following the tragedy of the Orbiter Columbia (STS-107) on February 1, 2003, a major effort commenced to develop a better understanding of debris impacts and their effect on the space shuttle subsystems. An initiative to develop and validate physics-based computer models to predict damage from such impacts was a fundamental component of this effort. To develop the models it was necessary to physically characterize reinforced carbon-carbon (RCC) along with ice and foam debris materials, which could shed on ascent and impact the orbiter RCC leading edges. The validated models enabled the launch system community to use the impact analysis software LS-DYNA (Livermore Software Technology Corp.) to predict damage by potential and actual impact events on the orbiter leading edge and nose cap thermal protection systems. Validation of the material models was done through a three-level approach: Level 1--fundamental tests to obtain independent static and dynamic constitutive model properties of materials of interest, Level 2--subcomponent impact tests to provide highly controlled impact test data for the correlation and validation of the models, and Level 3--full-scale orbiter leading-edge impact tests to establish the final level of confidence for the analysis methodology. This report discusses the Level 2 test program conducted in the NASA Glenn Research Center (GRC) Ballistic Impact Laboratory with ice projectile impact tests on flat RCC panels, and presents the data observed. The Level 2 testing consisted of 54 impact tests in the NASA GRC Ballistic Impact Laboratory on 6- by 6-in. and 6- by 12-in. flat plates of RCC and evaluated three types of debris projectiles: Single-crystal, polycrystal, and "soft" ice. These impact tests helped determine the level of damage generated in the RCC flat plates by each projectile and validated the use of the ice and RCC models for use in LS-DYNA.
Author
CARBON-CARBON COMPOSITES; COMPOSITE STRUCTURES; DYNAMIC MODELS; FLAT PLATES; ICE; IMPACT TESTS; MATHEMATICAL MODELS
20090042817 NASA Glenn Research Center, Cleveland, OH, United States
Engine Conceptual Design Studies for a Hybrid Wing Body Aircraft
Tong, Michael T.; Jones, Scott M.; Haller, William J.; Handschuh, Robert F.; November 2009; In English; ASME Turbo 2009, 8-12 Jun. 2009, Orlando, FL, United States; Original contains black and white illustrations
Contract(s)/Grant(s): WBS 561581.02.08.03.13.03
Report No.(s): NASA/TM-2009-215680; GT2009-59568; ARL-TR-4719; E-16910-1; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042817
Worldwide concerns of air quality and climate change have made environmental protection one of the most critical issues in aviation today. NASA s current Fundamental Aeronautics Research program is directed at three generations of aircraft in the near, mid and far term, with initial operating capability around 2015, 2020, and 2030, respectively. Each generation has associated goals for fuel burn, NOx, noise, and field-length reductions relative to today s aircrafts. The research for the 2020 generation is directed at enabling a hybrid wing body (HWB) aircraft to meet NASA s aggressive technology goals. This paper presents the conceptual cycle and mechanical designs of the two engine concepts, podded and embedded systems, which were proposed for a HWB cargo freighter. They are expected to offer significant benefits in noise reductions without compromising the fuel burn.
Author
ENGINE DESIGN; ENVIRONMENT PROTECTION; NITROGEN OXIDES; NOISE REDUCTION; AERONAUTICAL ENGINEERING; AIR QUALITY
20090042818 NASA Glenn Research Center, Cleveland, OH, United States
Advanced Noise Control Fan Aerodynamic Performance
Bozak, Richard F., Jr.; November 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 561581.02.08.03.18.02
Report No.(s): NASA/TM-2009-215807; E-17070; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042818
The Advanced Noise Control Fan at the NASA Glenn Research Center is used to experimentally analyze fan generated acoustics. In order to determine how a proposed noise reduction concept affects fan performance, flow measurements can be used to compute mass flow. Since tedious flow mapping is required to obtain an accurate mass flow, an equation was developed to correlate the mass flow to inlet lip wall static pressure measurements. Once this correlation is obtained, the mass flow for future configurations can be obtained from the nonintrusive wall static pressures. Once the mass flow is known, the thrust and fan performance can be evaluated. This correlation enables fan acoustics and performance to be obtained simultaneously without disturbing the flow.
Author
NOISE REDUCTION; AERODYNAMIC CHARACTERISTICS; INLET PRESSURE; STATIC PRESSURE; FLOW MEASUREMENT; FLOW DISTRIBUTION; MASS FLOW; ACOUSTICS
20090042819 NASA Glenn Research Center, Cleveland, OH, United States
Windage Power Loss in Gas Foil Bearings and the Rotor-Stator Clearance of High Speed Generators Operating in High Pressure Environments
Bruckner, Robert J.; November 2009; In English; ASME Turbo Expo 2009, 8-12 Jun. 2009, Orlando, FL, United States; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 877686.02.07.03.01.01.14
Report No.(s): NASA/TM-2009-215826; GT2009-60118; E-17088; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042819
Closed Brayton Cycle (CBC) and Closed Supercritical Cycle (CSC) engines are prime candidates to convert heat from a reactor into electric power for robotic space exploration and habitation. These engine concepts incorporate a permanent magnet starter/generator mounted on the engine shaft along with the requisite turbomachinery. Successful completion of the long-duration missions currently anticipated for these engines will require designs that adequately address all losses within the machine. The preliminary thermal management concept for these engine types is to use the cycle working fluid to provide the required cooling. In addition to providing cooling, the working fluid will also serve as the bearing lubricant. Additional requirements, due to the unique application of these microturbines, are zero contamination of the working fluid and entirely maintenance-free operation for many years. Losses in the gas foil bearings and within the rotor-stator gap of the generator become increasingly important as both rotational speed and mean operating pressure are increased. This paper presents the results of an experimental study, which obtained direct torque measurements on gas foil bearings and generator rotor-stator gaps. Test conditions for these measurements included rotational speeds up to 42,000 revolutions per minute, pressures up to 45 atmospheres, and test gases of nitrogen, helium, and carbon dioxide. These conditions provided a maximum test Taylor number of nearly one million. The results show an exponential rise in power loss as mean operating density is increased for both the gas foil bearing and generator windage. These typical "secondary" losses can become larger than the total system output power if conventional design paradigms are followed. A nondimensional analysis is presented to extend the experimental results into the CSC range for the generator windage.
Author
FOIL BEARINGS; BRAYTON CYCLE; CLOSED CYCLES; TURBOMACHINERY; HIGH PRESSURE; ROTORS; SHAFTS (MACHINE ELEMENTS)
20090042820 NASA Glenn Research Center, Cleveland, OH, United States
Bayes Analysis and Reliability Implications of Stress-Rupture Testing a Kevlar/Epoxy COPV Using Temperature and Pressure Acceleration
Phoenix, S. Leigh; Kezirian, Michael T.; Murthy, Pappu L. N.; November 2009; In English; 50th Structures, Structural Dynamics, and Materials Conference, 4-7 May 2009, Palm Springs, CA, United States; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 869021.03.03.02.01
Report No.(s): NASA/TM-2009-215830; AIAA Paper 2009-2569; E-17091; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042820
Composite Overwrapped Pressure Vessels (COPVs) that have survived a long service time under pressure generally must be recertified before service is extended. Flight certification is dependent on the reliability analysis to quantify the risk of stress rupture failure in existing flight vessels. Full certification of this reliability model would require a statistically significant number of lifetime tests to be performed and is impractical given the cost and limited flight hardware for certification testing purposes. One approach to confirm the reliability model is to perform a stress rupture test on a flight COPV. Currently, testing of such a Kevlar49 (Dupont)/epoxy COPV is nearing completion. The present paper focuses on a Bayesian statistical approach to analyze the possible failure time results of this test and to assess the implications in choosing between possible model parameter values that in the past have had significant uncertainty. The key uncertain parameters in this case are the actual fiber stress ratio at operating pressure, and the Weibull shape parameter for lifetime; the former has been uncertain due to ambiguities in interpreting the original and a duplicate burst test. The latter has been uncertain due to major differences between COPVs in the database and the actual COPVs in service. Any information obtained that clarifies and eliminates uncertainty in these parameters will have a major effect on the predicted reliability of the service COPVs going forward. The key result is that the longer the vessel survives, the more likely the more optimistic stress ratio model is correct. At the time of writing, the resulting effect on predicted future reliability is dramatic, increasing it by about one "nine," that is, reducing the predicted probability of failure by an order of magnitude. However, testing one vessel does not change the uncertainty on the Weibull shape parameter for lifetime since testing several vessels would be necessary.
Author
PRESSURE VESSELS; COMPOSITE WRAPPING; WEIBULL DENSITY FUNCTIONS; RELIABILITY ANALYSIS; STRESS ANALYSIS; EPOXY RESINS; KEVLAR (TRADEMARK); BAYES THEOREM
20090042821 NASA Glenn Research Center, Cleveland, OH, United States
The Case for Intelligent Propulsion Control for Fast Engine Response
Litt, Jonathan S.; Frederick, Dean K.; Guo, Ten-Huei; November 2009; In English; Infotech@Aerospace Conference, 6-9, Seattle, WA, United States
Contract(s)/Grant(s): WBS 457280.02.07.03.04.03
Report No.(s): NASA/TM-2009-215668; AIAA Paper 2009-1876; E-17010; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042821
Damaged aircraft have occasionally had to rely solely on thrust to maneuver as a consequence of losing hydraulic power needed to operate flight control surfaces. The lack of successful landings in these cases inspired research into more effective methods of utilizing propulsion-only control. That research demonstrated that one of the major contributors to the difficulty in landing is the slow response of the engines as compared to using traditional flight control. To address this, research is being conducted into ways of making the engine more responsive under emergency conditions. This can be achieved by relaxing controller limits, adjusting schedules, and/or redesigning the regulators to increase bandwidth. Any of these methods can enable faster response at the potential expense of engine life and increased likelihood of stall. However, an example sensitivity analysis revealed a complex interaction of the limits and the difficulty in predicting the way to achieve the fastest response. The sensitivity analysis was performed on a realistic engine model, and demonstrated that significantly faster engine response can be achieved compared to standard Bill of Material control. However, the example indicates the need for an intelligent approach to controller limit adjustment in order for the potential to be fulfilled.
Author
CONTROLLERS; FLIGHT CONTROL; ENGINE CONTROL; PROPULSION; REGULATORS; CONTROL SURFACES
20090042822 NASA Langley Research Center, Hampton, VA, United States
Pion Total Cross Section in Nucleon - Nucleon Collisions
Norbury, John W.; December 2009; In English; Original contains color illustrations
Contract(s)/Grant(s): WBS 651549.02.07.01
Report No.(s): NASA/TP-2009-215953; L-19597; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042822
Total cross section parameterizations for neutral and charged pion production in nucleon - nucleon collisions are compared to experimental data over the projectile momentum range from threshold to 300 GeV. Both proton - proton and proton - neutron reactions are considered. Overall excellent agreement between parameterizations and experiment is found, except for notable disagreements near threshold. In addition, the hypothesis that the neutral pion production cross section can be obtained from the average charged pion cross section is checked. The theoretical formulas presented in the paper obey this hypothesis for projectile momenta below 500 GeV. The results presented provide a test of engineering tools used to calculate the pion component of space radiation.
Author
PIONS; PARAMETERIZATION; PROTONS; NUCLEAR REACTIONS; EXTRATERRESTRIAL RADIATION; NEUTRONS; ATOMIC COLLISIONS
20090042823 NASA Langley Research Center, Hampton, VA, United States
Experimental Behavior of Fatigued Single Stiffener PRSEUS Specimens
Jegley, Dawn C.; December 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 699959.02.08.07.02.02
Report No.(s): NASA/TM-2009-215955; L-19782; LF99-9677; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042823
NASA, the Air Force Research Laboratory and The Boeing Company have worked to develop new low-cost, light-weight composite structures for aircraft. A Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) concept has been developed which offers advantages over traditional metallic structure. In this concept a stitched carbon-epoxy material system has been developed with the potential for reducing the weight and cost of transport aircraft structure by eliminating fasteners, thereby reducing part count and labor. By adding unidirectional carbon rods to the top of stiffeners, the panel becomes more structurally efficient. This combination produces a more damage tolerant design. This document describes the results of experimentation on PRSEUS specimens loaded in unidirectional compression in fatigue and to failure.
Author
COMPOSITE STRUCTURES; EPOXY MATRIX COMPOSITES; DURABILITY; MILITARY TECHNOLOGY; WEIGHT REDUCTION
20090042837 NASA Glenn Research Center, Cleveland, OH, United States
Concept for a Low-Cost, High-Efficiency Precipitation Radar System Based on Ferroelectric Reflectarray Antenna
Romanofsky, Robert; Mueller, Carl; Chandrasekar, Chandra V.; October 2009; In English; 2009 Radar Conference, 4-8 May 2009, Pasadena, CA, United States; Original contains color illustrations
Contract(s)/Grant(s): WBS 439432.04.04.01
Report No.(s): NASA/TM-2009-215663; E-17005; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042837
This work proposes a concept on a novel scanning phased array, based on thin film ferroelectric phase shifters, for an X-band precipitation monostatic radar.
Author
FERROELECTRICITY; ANTENNA ARRAYS; METEOROLOGICAL RADAR; SUPERHIGH FREQUENCIES; REFLECTOR ANTENNAS; PRECIPITATION (METEOROLOGY); LOW COST
20090042865 NASA Langley Research Center, Hampton, VA, United States
A Relationship Between Constraint and the Critical Crack Tip Opening Angle
Johnston, William M.; James, Mark A.; December 2009; In English; Original contains black and white illustrations
Contract(s)/Grant(s): NNL07AA00B; NNL078M74TWBS 658259.02.07.07.03
Report No.(s): NASA/CR-2009-215930; LF99-9198; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042865
Of the various approaches used to model and predict fracture, the Crack Tip Opening Angle (CTOA) fracture criterion has been successfully used for a wide range of two-dimensional thin-sheet and thin plate applications. As thicker structure is considered, modeling the full three-dimensional fracture process will become essential. This paper investigates relationships between the local CTOA evaluated along a three-dimensional crack front and the corresponding local constraint. Previously reported tunneling crack front shapes were measured during fracture by pausing each test and fatigue cycling the specimens to mark the crack surface. Finite element analyses were run to model the tunneling shape during fracture, with the analysis loading conditions duplicating those tests. The results show an inverse relationship between the critical fracture value and constraint which is valid both before maximum load and after maximum load.
Author
CRACK TIPS; MATHEMATICAL MODELS; MECHANICAL PROPERTIES; CONSTRAINTS; FRACTURE MECHANICS
Additions to the NASA Aeronautics and Space Database as of 01/04/2010
20090042972 NASA Langley Research Center, Hampton, VA, United States
Comparison of Transport Codes, HZETRN, HETC and FLUKA, Using 1977 GCR Solar Minimum Spectra
Heinbockel, John H.; Slaba, Tony C.; Tripathi, Ram K.; Blattnig, Steve R.; Norbury, John W.; Badavi, Francis F.; Townsend, Lawrence W.; Handler, Thomas; Gabriel, Tony A.; Pinsky, Lawrence S.; Reddell, Brandon; Aumann, Aric R.; December 2009; In English; Original contains color illustrations
Contract(s)/Grant(s): NNL07AA36C; NNL07AA18CNNL06AA14A651549.02.07.01
Report No.(s): NASA/TP-2009-215956; L-19753; LF99-9385; Copyright; Avail.: CASI: A05, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042972
The HZETRN deterministic radiation transport code is one of several tools developed to analyze the effects of harmful galactic cosmic rays (GCR) and solar particle events (SPE) on mission planning, astronaut shielding and instrumentation. This paper is a comparison study involving the two Monte Carlo transport codes, HETC-HEDS and FLUKA, and the deterministic transport code, HZETRN. Each code is used to transport ions from the 1977 solar minimum GCR spectrum impinging upon a 20 g/cm2 Aluminum slab followed by a 30 g/cm2 water slab. This research is part of a systematic effort of verification and validation to quantify the accuracy of HZETRN and determine areas where it can be improved. Comparisons of dose and dose equivalent values at various depths in the water slab are presented in this report. This is followed by a comparison of the proton fluxes, and the forward, backward and total neutron fluxes at various depths in the water slab. Comparisons of the secondary light ion 2H, 3H, 3He and 4He fluxes are also examined.
Author
GALACTIC COSMIC RAYS; SOLAR ACTIVITY EFFECTS; SOLAR STORMS; RADIATION TRANSPORT; MONTE CARLO METHOD; MISSION PLANNING; SOLAR CORPUSCULAR RADIATION
20090042975 NASA Langley Research Center, Hampton, VA, United States
Development of Quiet Honeycomb Panels
Palumbo, Daniel L.; Klos, Jacob; December 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 561581.02.08.07.18.02
Report No.(s): NASA/TM-2009-215954; L-19785; LF99-9714; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042975
Sandwich honeycomb composite panels are lightweight and strong, and, therefore, provide a reasonable alternative to the aluminum ring framelstringer architecture currently used for most aircraft airframes. The drawback to honeycomb panels is that they radiate noise into the aircraft cabin very efficiently provoking the need for additional sound treatment which adds weight and reduces the material's cost advantage. A series of honeycomb panels were made which incorporated different design strategies aimed at reducing the honeycomb panels' radiation efficiency while at the same time maintaining its strength. The majority of the desi gns were centered around the concept of creatin g areas of reduced stiffness in the panel by adding voids and recesses to the core. The effort culminated with a reinforced./recessed panel which had 6 dB higher transmission loss than the baseline solid core panel while maintaining comparable strength.
Author
HONEYCOMB STRUCTURES; SANDWICH STRUCTURES; PANELS; AIRFRAMES; COMPOSITE STRUCTURES
20090042976 NASA Langley Research Center, Hampton, VA, United States
Version 2 of the Protuberance Correlations for the Shuttle-Orbiter Boundary Layer Transition Tool
King, Rudolph A.; Kegerise, Michael A.; Berry, Scott A.; December 2009; In English; Original contains color illustrations
Contract(s)/Grant(s): WBS 599489.02.07.07.04.11.01
Report No.(s): NASA/TP-2009-215951; LF99-9855; L-19791; No Copyright; Avail.: CASI: A04, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042976
Orbiter-specific transition data, acquired in four ground-based facilities (LaRC 20-Inch Mach 6 Air Tunnel, LaRC 31-Inch Mach 10 Air Tunnel, LaRC 20-Inch Mach 6 CF4 Tunnel, and CUBRC LENS-I Shock Tunnel) with three wind tunnel model scales (0.75, 0.90, and 1.8%) and from Orbiter historical flight data, have been analyzed to improve a pre-existing engineering tool for reentry transition prediction on the windward side of the Orbiter. Boundary layer transition (BLT) engineering correlations for transition induced by isolated protuberances are presented using a laminar Navier-Stokes (N-S) database to provide the relevant boundary-layer properties. It is demonstrated that the earlier version of the BLT correlation that had been developed using parameters derived from an engineering boundary-layer code has improved data collapse when developed with the N-S database. Of the new correlations examined, the proposed correlation 5, based on boundary-layer edge and wall properties, was found to provide the best overall correlation metrics when the entire database is employed. The second independent correlation (proposed correlation 7) selected is based on properties within the boundary layer at the protuberance height. The Aeroheating Panel selected a process to derive the recommended coefficients for Version 2 of the BLT Tool. The assumptions and limitations of the recommended protuberance BLT Tool V.2 are presented.
Author
BOUNDARY LAYER TRANSITION; SPACE SHUTTLE ORBITERS; CORRELATION; AERODYNAMIC HEATING; HYPERSONIC SPEED; PROTUBERANCES
20090042984 NASA Langley Research Center, Hampton, VA, United States
Turbulent Wing-Leading-Edge Correlation Assessment for the Shuttle Orbiter
King, Rudolph A.; Vaughan, Matthew P.; December 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 599489.02.07.07.04.11.01
Report No.(s): NASA/TM-2009-215949; L-19784; LF99-9713; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20090042984
This study was conducted in support of the Orbiter damage assessment activity that takes place for each Shuttle mission since STS-107 (STS - Space Transportation System). As part of the damage assessment activity, the state of boundary layer (laminar or turbulent) during reentry needs to be estimated in order to define the aerothermal environment on the Orbiter. Premature turbulence on the wing leading edge (WLE) is possible if a surface irregularity promotes early transition and the resulting turbulent wedge flow contaminates the WLE flow. The objective of this analysis is to develop a criterion to determine if and when the flow along the WLE experiences turbulent heating given an incoming turbulent boundary layer that contaminates the attachment line. The data to be analyzed were all obtained as part of the MH-13 Space Shuttle Orbiter Aerothermodynamic Test conducted on a 1.8%-scale Orbiter model at Calspan/University of Buffalo Research Center in the Large Energy National Shock Tunnels facility. A rational framework was used to develop a means to assess the state of the WLE flow on the Orbiter during reentry given a contaminated attachment-line flow. Evidence of turbulent flow on the WLE has been recently documented for a few STS missions during the Orbiter s flight history, albeit late in the reentry trajectory. The criterion developed herein will be compared to these flight results.
Author
SPACE SHUTTLE ORBITERS; BOUNDARY LAYERS; TURBULENT BOUNDARY LAYER; SPACE TRANSPORTATION SYSTEM; DAMAGE ASSESSMENT; LEADING EDGES; REENTRY TRAJECTORIES; CONTAMINANTS
Additions to the NASA Aeronautics and Space Database as of 01/18/2010
20100000016 NASA Glenn Research Center, Cleveland, OH, United States
An Object-Oriented Computer Code for Aircraft Engine Weight Estimation
Tong, Michael T.; Naylor, Bret A.; December 2009; In English; Gas Turbine Technical Congress and Exposition (Turbo Expo 2008), 9-13 Jun. 2008, Berlin, Germany; Original contains black and white illustrations
Contract(s)/Grant(s): WBS 561581.02.08.03.13.03
Report No.(s): NASA/TM-2009-215656; GT2008-50062; E-916428-1; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100000016
Reliable engine-weight estimation at the conceptual design stage is critical to the development of new aircraft engines. It helps to identify the best engine concept amongst several candidates. At NASA Glenn Research Center (GRC), the Weight Analysis of Turbine Engines (WATE) computer code, originally developed by Boeing Aircraft, has been used to estimate the engine weight of various conceptual engine designs. The code, written in FORTRAN, was originally developed for NASA in 1979. Since then, substantial improvements have been made to the code to improve the weight calculations for most of the engine components. Most recently, to improve the maintainability and extensibility of WATE, the FORTRAN code has been converted into an object-oriented version. The conversion was done within the NASA's NPSS (Numerical Propulsion System Simulation) framework. This enables WATE to interact seamlessly with the thermodynamic cycle model which provides component flow data such as airflows, temperatures, and pressures, etc., that are required for sizing the components and weight calculations. The tighter integration between the NPSS and WATE would greatly enhance system-level analysis and optimization capabilities. It also would facilitate the enhancement of the WATE code for next-generation aircraft and space propulsion systems. In this paper, the architecture of the object-oriented WATE code (or WATE++) is described. Both the FORTRAN and object-oriented versions of the code are employed to compute the dimensions and weight of a 300-passenger aircraft engine (GE90 class). Both versions of the code produce essentially identical results as should be the case.
Author
TURBINE ENGINES; ENGINE DESIGN; OBJECT-ORIENTED PROGRAMMING; PROPULSION SYSTEM PERFORMANCE; PROPULSION SYSTEM CONFIGURATIONS; WEIGHT ANALYSIS; MAINTAINABILITY
20100000017 NASA Glenn Research Center, Cleveland, OH, United States
Integrity of the Plasma Magnetic Nozzle
Gerwin, Richard A.; December 2009; In English; Original contains black and white illustrations
Contract(s)/Grant(s): NASA Order C-32057-GWBS 22-973-90-01
Report No.(s): NASA/TP-2009-213439; E-14974; No Copyright; Avail.: CASI: A06, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100000017
This report examines the physics governing certain aspects of plasma propellant flow through a magnetic nozzle, specifically the integrity of the interface between the plasma and the nozzle s magnetic field. The injection of 100s of eV plasma into a magnetic flux nozzle that converts thermal energy into directed thrust is fundamental to enabling 10 000s of seconds specific impulse and 10s of kW/kg specific power piloted interplanetary propulsion. An expression for the initial thickness of the interface is derived and found to be approx.10(exp -2) m. An algorithm is reviewed and applied to compare classical resistivity to gradient-driven microturbulent (anomalous) resistivity, in terms of the spatial rate and time integral of resistive interface broadening, which can then be related to the geometry of the nozzle. An algorithm characterizing plasma temperature, density, and velocity dependencies is derived and found to be comparable to classical resistivity at local plasma temperatures of approx. 200 eV. Macroscopic flute-mode instabilities in regions of "adverse magnetic curvature" are discussed; a growth rate formula is derived and found to be one to two e-foldings of the most unstable Rayleigh-Taylor (RT) mode. After establishing the necessity of incorporating the Hall effect into Ohm s law (allowing full Hall current to flow and concomitant plasma rotation), a critical nozzle length expression is derived in which the interface thickness is limited to about 1 ion gyroradius.
Author
MAGNETIC NOZZLES; PLASMAS (PHYSICS); PROPELLANTS; MAGNETIC FIELDS; THERMAL ENERGY; MAGNETOHYDRODYNAMIC FLOW; SPECIFIC IMPULSE; INTERPLANETARY SPACECRAFT
20100000018 NASA Glenn Research Center, Cleveland, OH, United States
A Noninvasive Miniaturized-Wireless Laser-Doppler Fiber-Optic Sensor for Understanding Distal Fingertip Injuries in Astronauts
Ansari, Rafat R.; Jones, Jeffrey A.; Pollonini, Luca; Rodriquez, Mikael; Opperman, Roedolph; Hochstein, Jason; December 2009; In English; Photonics West (International Society for Optical Engineering (SPIE), 24 -29 Jan. 2009, San Jose, CA, United States; Original contains color illustrations
Contract(s)/Grant(s): WBS 599891.01.03.01WBS 599891.01.03.01
Report No.(s): NASA/TM-2009-215679; E-17045; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100000018
During extra-vehicular activities (EVAs) or spacewalks astronauts over use their fingertips under pressure inside the confined spaces of gloves/space suits. The repetitive hand motion is a probable cause for discomfort and injuries to the fingertips. We describe a new wireless fiber-optic probe that can be integrated inside the astronaut glove for noninvasive blood perfusion measurements in distal fingertips. In this preliminary study, we present blood perfusion measurements while performing hand-grip exercises simulating the use of space tools.
Author
EXTRAVEHICULAR ACTIVITY; GLOVES; SPACE SUITS; FINGERS; FIBER OPTICS; INJURIES; MINIATURIZATION; ASTRONAUTS
20100000019 NASA Glenn Research Center, Cleveland, OH, United States
The Development of Wheels for the Lunar Roving Vehicle
Asnani, Vivake; Delap, Damon; Creager, Colin; December 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 140765.04.02.01.02.03
Report No.(s): NASA/TM-2009-215798; E-17060; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100000019
The Lunar Roving Vehicle (LRV) was developed for NASA s Apollo program so astronauts could cover a greater range on the lunar surface, carry more science instruments, and return more soil and rock samples than by foot. Because of the unique lunar environment, the creation of flexible wheels was the most challenging and time consuming aspect of the LRV development. Wheels developed for previous lunar systems were not sufficient for use with this manned vehicle; therefore, several new designs were created and tested. Based on criteria set by NASA, the choices were narrowed down to two: the wire mesh wheel developed by General Motors (GM), and the hoop spring wheel developed by the Bendix Corporation. Each of these underwent intensive mechanical, material, and terramechanical analyses, and in the end, the wire mesh wheel was chosen for the LRV. Though the wire mesh wheel was determined to be the best choice for its particular application, it may be insufficient towards achieving the objectives of future lunar missions that could require higher tractive capability, increased weight capacity, or extended life. Therefore lessons learned from the original LRV wheel development and suggestions for future Moon wheel projects are offered.
Author
LUNAR ROVING VEHICLES; WHEELS; LUNAR ENVIRONMENT; LUNAR SURFACE; LESSONS LEARNED
20100000020 NASA Glenn Research Center, Cleveland, OH, United States
Simulated Tip Rub Testing of Low-Density Metal Foam
Bowman, Cheryl L.; Jones, Michael G.; December 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 561581.02.08.03.15.03
Report No.(s): NASA/TM-2009-215818; E-17080; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100000020
Preliminary acoustic studies have indicated that low-density, open-cell, metal foams may be suitable acoustic liner material for noise suppression in high by-pass engines. Metal foam response under simulated tip rub conditions was studied to assess whether its durability would be sufficient for the foam to serve both as a rub strip above the rotor as well as an acoustic treatment. Samples represented four metal alloys, nominal cell dimensions ranging from 60 to 120 cells per inch (cpi), and relative densities ranging from 3.4 to 10 percent. The resulting rubbed surfaces were relatively smooth and the open cell structure of the foam was not adversely affected. Sample relative density appeared to have significant influence on the forces induced by the rub event. Acoustic responses of various surface preparations were measured using a normal incidence tube. The results of this study indicate that the foam s open-cell structure was retained after rubbing and that the acoustic absorption spectra variation was minimal.
Author
METAL FOAMS; POROSITY; ACOUSTIC ATTENUATION; ACOUSTIC PROPERTIES; ABSORPTION SPECTRA; DURABILITY
20100000021 NASA Glenn Research Center, Cleveland, OH, United States
An Investigation of Ionic Wind Propulsion
Wilson, Jack; Perkins, Hugh D.; Thompson, William K.; December 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 561581.02.08.03.13.05
Report No.(s): NASA/TM-2009-215822; E-17084; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100000021
A corona discharge device generates an ionic wind and thrust, when a high voltage corona discharge is struck between sharply pointed electrodes and larger radius ground electrodes. The objective of this study was to examine whether this thrust could be scaled to values of interest for aircraft propulsion. An initial experiment showed that the thrust observed did equal the thrust of the ionic wind. Different types of high voltage electrodes were tried, including wires, knife-edges, and arrays of pins. A pin array was found to be optimum. Parametric experiments, and theory, showed that the thrust per unit power could be raised from early values of 5 N/kW to values approaching 50 N/kW, but only by lowering the thrust produced, and raising the voltage applied. In addition to using DC voltage, pulsed excitation, with and without a DC bias, was examined. The results were inconclusive as to whether this was advantageous. It was concluded that the use of a corona discharge for aircraft propulsion did not seem very practical.
Author
ION PROPULSION; ELECTRIC CORONA; THRUST; ELECTRIC POTENTIAL; HIGH VOLTAGES
20100000027 NASA Glenn Research Center, Cleveland, OH, United States
An Overview of Prognosis Health Management Research at Glenn Research Center for Gas Turbine Engine Structures With Special Emphasis on Deformation and Damage Modeling
Arnold, Steven M.; Goldberg, Robert K.; Lerch, Bradley A.; Saleeb, Atef F.; December 2009; In English; FROM Annual Conference of the Prognostics and Health Management Society 2009, 27 Sep. - 1 Oct. 2009, San Diego, CA, United States; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 645846.02.02.03.03
Report No.(s): NASA/TM-2009-215827/REV 1; E-17089; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100000027
Herein a general, multimechanism, physics-based viscoelastoplastic model is presented in the context of an integrated diagnosis and prognosis methodology which is proposed for structural health monitoring, with particular applicability to gas turbine engine structures. In this methodology, diagnostics and prognostics will be linked through state awareness variable(s). Key technologies which comprise the proposed integrated approach include (1) diagnostic/detection methodology, (2) prognosis/lifing methodology, (3) diagnostic/prognosis linkage, (4) experimental validation, and (5) material data information management system. A specific prognosis lifing methodology, experimental characterization and validation and data information management are the focal point of current activities being pursued within this integrated approach. The prognostic lifing methodology is based on an advanced multimechanism viscoelastoplastic model which accounts for both stiffness and/or strength reduction damage variables. Methods to characterize both the reversible and irreversible portions of the model are discussed. Once the multiscale model is validated the intent is to link it to appropriate diagnostic methods to provide a full-featured structural health monitoring system.
Author
PROGNOSIS; GAS TURBINE ENGINES; DIAGNOSIS; INFORMATION MANAGEMENT; STRUCTURAL HEALTH MONITORING; DAMAGE; ELASTOPLASTICITY; DEFORMATION
20100000028 NASA Glenn Research Center, Cleveland, OH, United States
Analysis of Electromagnetic Wave Propagation in a Magnetized Re-Entry Plasma Sheath Via the Kinetic Equation
Manning, Robert M.; December 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 599489.02.07.03.04.02.02
Report No.(s): NASA/TM-2009-216096; E-17149; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100000028
Based on a theoretical model of the propagation of electromagnetic waves through a hypersonically induced plasma, it has been demonstrated that the classical radiofrequency communications blackout that is experienced during atmospheric reentry can be mitigated through the appropriate control of an external magnetic field of nominal magnitude. The model is based on the kinetic equation treatment of Vlasov and involves an analytical solution for the electric and magnetic fields within the plasma allowing for a description of the attendant transmission, reflection and absorption coefficients. The ability to transmit through the magnetized plasma is due to the magnetic windows that are created within the plasma via the well-known whistler modes of propagation. The case of 2 GHz transmission through a re-entry plasma is considered. The coefficients are found to be highly sensitive to the prevailing electron density and will thus require a dynamic control mechanism to vary the magnetic field as the plasma evolves through the re-entry phase.
Author
WAVE PROPAGATION; ELECTROMAGNETIC WAVE TRANSMISSION; RADIO TRANSMISSION; RADIO FREQUENCIES; MICROWAVE TRANSMISSION; ABSORPTIVITY
20100000129 NASA Glenn Research Center, Cleveland, OH, United States
Failure Analysis of Sapphire Refractive Secondary Concentrators
Salem, Jonathan A.; Quinn, George D.; December 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 984754.02.07.03.16.03; WBS 441261.04.22.04.02
Report No.(s): NASA/TM-2009-215802; E-17063; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100000129
Failure analysis was performed on two sapphire, refractive secondary concentrators (RSC) that failed during elevated temperature testing. Both concentrators failed from machining/handling damage on the lens face. The first concentrator, which failed during testing to 1300 C, exhibited a large r-plane twin extending from the lens through much of the cone. The second concentrator, which was an attempt to reduce temperature gradients and failed during testing to 649 C, exhibited a few small twins on the lens face. The twins were not located at the origin, but represent another mode of failure that needs to be considered in the design of sapphire components. In order to estimate the fracture stress from fractographic evidence, branching constants were measured on sapphire strength specimens. The fractographic analysis indicated radial tensile stresses of 44 to 65 MPa on the lens faces near the origins. Finite element analysis indicated similar stresses for the first RSC, but lower stresses for the second RSC. Better machining and handling might have prevented the fractures, however, temperature gradients and resultant thermal stresses need to be reduced to prevent twinning.
Author
SAPPHIRE; THERMAL STRESSES; FAILURE ANALYSIS; TWINNING; FRACTURES (MATERIALS); CONCENTRATORS; TENSILE STRESS; TEMPERATURE GRADIENTS; FRACTOGRAPHY
Additions to the NASA Aeronautics and Space Database as of 01/21/2010
20100001322 NASA Glenn Research Center, Cleveland, OH, United States
Progress Towards the Remote Sensing of Aircraft Icing Hazards
Reehorst, Andrew; Brinker, David; Politovich, Marcia; Serke, David; Ryerson, Charles; Pazmany, Andrew; Solheim, Fredrick; November 2009; In English; Optics and Photonics, 10-14 Aug. 2008, San Diego, CA, United States; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 609866.02.07.03.04
Report No.(s): NASA/TM-2009-215828; E-17090; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100001322
NASA has teamed with the FAA, DoD, industry, and academia for research into the remote detection and measurement of atmospheric conditions leading to aircraft icing hazards. The ultimate goal of this effort is to provide pilots, controllers, and dispatchers sufficient information to allow aircraft to avoid or minimize their exposure to the hazards of in-flight icing. Since the hazard of in-flight icing is the outcome of aircraft flight through clouds containing supercooled liquid water and strongly influenced by the aircraft s speed and configuration and by the length of exposure, the hazard cannot be directly detected, but must be inferred based upon the measurement of conducive atmospheric conditions. Therefore, icing hazard detection is accomplished through the detection and measurement of liquid water in regions of measured sub-freezing air temperatures. The icing environment is currently remotely measured from the ground with a system fusing radar, lidar, and multifrequency microwave radiometer sensors. Based upon expected ice accretion severity for the measured environment, a resultant aircraft hazard is then calculated. Because of the power, size, weight, and view angle constraints of airborne platforms, the current ground-based solution is not applicable for flight. Two current airborne concepts are based upon the use of either multifrequency radiometers or multifrequency radar. Both ground-based and airborne solutions are required for the future since groundbased systems can provide hazard detection for all aircraft in airport terminal regions while airborne systems will be needed to provide equipped aircraft with flight path coverage between terminal regions.
Author
AIRCRAFT ICING; OPTICAL RADAR; HAZARDS; MICROWAVE RADIOMETERS; DETECTION; REMOTE SENSING; FREEZING
Additions to the NASA Aeronautics and Space Database as of 01/29/2010
20100002216 NASA Langley Research Center, Hampton, VA, United States
Boundary Closures for Fourth-order Energy Stable Weighted Essentially Non-Oscillatory Finite Difference Schemes
Fisher, Travis C.; Carpenter, Mark H.; Yamaleev, Nail K.; Frankel, Steven H.; December 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 599489.02.07.07.03.13.01
Report No.(s): NASA/TM-2009-216166; L-19792; LF99-9878; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100002216
A general strategy exists for constructing Energy Stable Weighted Essentially Non Oscillatory (ESWENO) finite difference schemes up to eighth-order on periodic domains. These ESWENO schemes satisfy an energy norm stability proof for both continuous and discontinuous solutions of systems of linear hyperbolic equations. Herein, boundary closures are developed for the fourth-order ESWENO scheme that maintain wherever possible the WENO stencil biasing properties, while satisfying the summation-by-parts (SBP) operator convention, thereby ensuring stability in an L2 norm. Second-order, and third-order boundary closures are developed that achieve stability in diagonal and block norms, respectively. The global accuracy for the second-order closures is three, and for the third-order closures is four. A novel set of non-uniform flux interpolation points is necessary near the boundaries to simultaneously achieve 1) accuracy, 2) the SBP convention, and 3) WENO stencil biasing mechanics.
Author
FINITE DIFFERENCE THEORY; ESSENTIALLY NON-OSCILLATORY SCHEMES; LINEAR EQUATIONS; HYPERBOLIC DIFFERENTIAL EQUATIONS; PROVING
Additions to the NASA Aeronautics and Space Database as of 02/02/2010
20100002764 NASA Langley Research Center, Hampton, VA, United States
Constellation Program (CxP) Crew Exploration Vehicle (CEV) Project Integrated Landing System
Baker, John D.; Yuchnovicz, Daniel E.; Eisenman, David J.; Peer, Scott G.; Fasanella, Edward L.; Lawrence, Charles; December 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 869021.05.07.07.06
Report No.(s): NASA/TM-2009-216165; NESC-RP-06-060; L-19798; LF99-9958; No Copyright; Avail.: CASI: A14, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100002764
Crew Exploration Vehicle (CEV) Chief Engineer requested a risk comparison of the Integrated Landing System design developed by NASA and the design developed by Contractor- referred to as the LM 604 baseline. Based on the results of this risk comparison, the CEV Chief engineer requested that the NESC evaluate identified risks and develop strategies for their reduction or mitigation. The assessment progressed in two phases. A brief Phase I analysis was performed by the Water versus Land-Landing Team to compare the CEV Integrated Landing System proposed by the Contractor against the NASA TS-LRS001 baseline with respect to risk. A phase II effort examined the areas of critical importance to the overall landing risk, evaluating risk to the crew and to the CEV Crew Module (CM) during a nominal land-landing. The findings of the assessment are contained in this report.
Author
CREW EXPLORATION VEHICLE; CONSTELLATION PROGRAM; SYSTEMS ENGINEERING; LANDING AIDS; SPACECRAFT MODULES; SYSTEMS INTEGRATION; SPACECREWS
20100002800 NASA Langley Research Center, Hampton, VA, United States
Design and Manufacture of Structurally Efficient Tapered Struts
Brewster, Jebediah W.; December 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): NNL04AA12B; NNL08AD07TWBS 727950.04.05.23
Report No.(s): NASA/CR-2009-215957; LF99-8393; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100002800
Composite materials offer the potential of weight savings for numerous spacecraft and aircraft applications. A composite strut is just one integral part of the node-to-node system and the optimization of the shut and node assembly is needed to take full advantage of the benefit of composites materials. Lockheed Martin designed and manufactured a very light weight one piece composite tapered strut that is fully representative of a full scale flight article. In addition, the team designed and built a prototype of the node and end fitting system that will effectively integrate and work with the full scale flight articles.
Author
COMPOSITE MATERIALS; STRUTS; FITTING; TAPERING
Additions to the NASA Aeronautics and Space Database as of 02/03/2010
20100002886 NASA Glenn Research Center, Cleveland, OH, United States
Biofuels as an Alternative Energy Source for Aviation-A Survey
McDowellBomani, Bilal M.; Bulzan, Dan L.; Centeno-Gomez, Diana I.; Hendricks, Robert C.; December 2009; In English; Original contains color illustrations
Contract(s)/Grant(s): WBS 561581.02.08.03.16.02
Report No.(s): NASA/TM-2009-215587; E-16828; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100002886
The use of biofuels has been gaining in popularity over the past few years because of their ability to reduce the dependence on fossil fuels. As a renewable energy source, biofuels can be a viable option for sustaining long-term energy needs if they are managed efficiently. We investigate past, present, and possible future biofuel alternatives currently being researched and applied around the world. More specifically, we investigate the use of ethanol, cellulosic ethanol, biodiesel (palm oil, algae, and halophytes), and synthetic fuel blends that can potentially be used as fuels for aviation and nonaerospace applications. We also investigate the processing of biomass via gasification, hydrolysis, and anaerobic digestion as a way to extract fuel oil from alternative biofuels sources.
Author
ETHYL ALCOHOL; FOSSIL FUELS; RENEWABLE ENERGY; SYNTHETIC FUELS; BIOCONVERSION; HYDROLYSIS; FUEL OILS
20100002888 NASA Glenn Research Center, Cleveland, OH, United States
Integrated High Payoff Rocket Propulsion Technology (IHPRPT) SiC Recession Model
Opila, E. J.; December 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 599489.02.07.03.02.04.01
Report No.(s): NASA/TM-2009-215650; E-16962; No Copyright; Avail.: CASI: A04, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100002888
SiC stability and recession rates were modeled in hydrogen/oxygen combustion environments for the Integrated High Payoff Rocket Propulsion Technology (IHPRPT) program. The IHPRPT program is a government and industry program to improve U.S. rocket propulsion systems. Within this program SiC-based ceramic matrix composites are being considered for transpiration cooled injector faceplates or rocket engine thrust chamber liners. Material testing under conditions representative of these environments was conducted at the NASA Glenn Research Center, Cell 22. For the study described herein, SiC degradation was modeled under these Cell 22 test conditions for comparison to actual test results: molar mixture ratio, MR (O2:H2) = 6, material temperatures to 1700 C, combustion gas pressures between 0.34 and 2.10 atm, and gas velocities between 8,000 and 12,000 fps. Recession was calculated assuming rates were controlled by volatility of thermally grown silica limited by gas boundary layer transport. Assumptions for use of this model were explored, including the presence of silica on the SiC surface, laminar gas boundary layer limited volatility, and accuracy of thermochemical data for volatile Si-O-H species. Recession rates were calculated as a function of temperature. It was found that at 1700 C, the highest temperature considered, the calculated recession rates were negligible, about 200 m/h, relative to the expected lifetime of the material. Results compared favorably to testing observations. Other mechanisms contributing to SiC recession are briefly described including consumption of underlying carbon and pitting. A simple expression for liquid flow on the material surface was developed from a one-dimensional treatment of the Navier-Stokes Equation. This relationship is useful to determine under which conditions glassy coatings or thermally grown silica would flow on the material surface, removing protective layers by shear forces. The velocity of liquid flow was found to depend on the gas velocity, the viscosity of gas and liquid, as well as the thickness of the gas boundary layer and the liquid layer. Calculated flow rates of a borosilicate glass coating compared well to flow rates observed for this coating tested on a SiC panel in Cell 22.
Author
SILICON DIOXIDE; ROCKET ENGINES; COMBUSTION; THERMOCHEMISTRY; LAMINAR BOUNDARY LAYER; PROPULSION; THRUST CHAMBERS; GAS VISCOSITY; GAS TRANSPORT; FLOW VELOCITY; CERAMIC MATRIX COMPOSITES
20100002889 NASA Glenn Research Center, Cleveland, OH, United States
Integrated Vehicle Health Management Project-Modeling and Simulation for Wireless Sensor Applications
Wallett, Thomas M.; Mueller, Carl H.; Griner, James H., Jr.; December 2009; In English; Original contains black and white illustrations
Contract(s)/Grant(s): WBS 645846.03.07.03.05
Report No.(s): NASA/TM-2009-215833; E-17095; Copyright; Avail.: CASI: A02, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100002889
This paper describes the efforts in modeling and simulating electromagnetic transmission and reception as in a wireless sensor network through a realistic wing model for the Integrated Vehicle Health Management project at the Glenn Research Center. A computer model in a standard format for an S-3 Viking aircraft was obtained, converted to a Microwave Studio software format, and scaled to proper dimensions in Microwave Studio. The left wing portion of the model was used with two antenna models, one transmitting and one receiving, to simulate radio frequency transmission through the wing. Transmission and reception results were inconclusive.
Author
RADIO FREQUENCIES; S-3 AIRCRAFT; MICROWAVES; COMPUTERIZED SIMULATION; SIMULATION
20100002892 NASA Glenn Research Center, Cleveland, OH, United States
Meteoroid and Orbital Debris Threats to NASA's Docking Seals: Initial Assessment and Methodology
deGroh, Henry C., III; Gallo, Christopher A.; Nahra, Henry K.; December 2009; In English; 1st Atmospheric and Space Environments Conference, 22-25 Jun. 2009, San Antonio, TX, United States; Original contains color and black and white illustrations
Report No.(s): NASA/TM-2009-215835; AIAA Paper 2009-3524; E-170374; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100002892
The Crew Exploration Vehicle (CEV) will be exposed to the Micrometeoroid Orbital Debris (MMOD) environment in Low Earth Orbit (LEO) during missions to the International Space Station (ISS) and to the micrometeoroid environment during lunar missions. The CEV will be equipped with a docking system which enables it to connect to ISS and the lunar module known as Altair; this docking system includes a hatch that opens so crew and supplies can pass between the spacecrafts. This docking system is known as the Low Impact Docking System (LIDS) and uses a silicone rubber seal to seal in cabin air. The rubber seal on LIDS presses against a metal flange on ISS (or Altair). All of these mating surfaces are exposed to the space environment prior to docking. The effects of atomic oxygen, ultraviolet and ionizing radiation, and MMOD have been estimated using ground based facilities. This work presents an initial methodology to predict meteoroid and orbital debris threats to candidate docking seals being considered for LIDS. The methodology integrates the results of ground based hypervelocity impacts on silicone rubber seals and aluminum sheets, risk assessments of the MMOD environment for a variety of mission scenarios, and candidate failure criteria. The experimental effort that addressed the effects of projectile incidence angle, speed, mass, and density, relations between projectile size and resulting crater size, and relations between crater size and the leak rate of candidate seals has culminated in a definition of the seal/flange failure criteria. The risk assessment performed with the BUMPER code used the failure criteria to determine the probability of failure of the seal/flange system and compared the risk to the allotted risk dictated by NASA s program requirements.
Author
AEROSPACE ENVIRONMENTS; CRATERS; PROJECTILES; LEAKAGE; ELASTOMERS; MICROMETEOROIDS; SPACE DEBRIS; METEOROID HAZARDS; LOW EARTH ORBITS; RISK ASSESSMENT
20100002893 NASA Glenn Research Center, Cleveland, OH, United States
Status of the NEXT Long-Duration Test After 23,300 Hours of Operation
Herman, Daniel A.; Soulas, George C.; Patterson, Michael J.; December 2009; In English; 45th Joint Propulsion Conference and Exhibit, 2-5 Aug. 2009, Denver, CO, United States; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 346620.04.08.02.02.01
Report No.(s): NASA/TM-2009-215837; AIAA Paper 2009-4917; E-17097; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100002893
The NASA s Evolutionary Xenon Thruster (NEXT) program is developing the next-generation ion propulsion system with significant enhancements beyond the state-of-the-art in ion propulsion to provide future NASA science missions with enhanced mission capabilities at a low total development cost. As part of a comprehensive thruster service life assessment utilizing both testing and analyses, a Long-Duration Test (LDT) was initiated in June 2005, to verify the NEXT propellant throughput capability to a qualification-level of 450 kg, 1.5 times the anticipated throughput requirement of 300 kg per thruster from mission analyses. The LDT is being conducted with a modified, flight-representative NEXT engineering model ion thruster, designated EM3. As of July 2009, the thruster has accumulated 23,300 h of operation with extensive durations at the following input powers: 6.9, 4.7, 1.1, and 0.5 kW. The thruster has processed 427 kg of xenon surpassing the NSTAR propellant throughput demonstrated during the extended life testing of the Deep Space 1 flight spare ion thruster and approaching the NEXT development qualification throughput goal. The NEXT LDT has demonstrated a total impulse of 16.0 10(exp 6) N/s; the highest total impulse ever demonstrated by an ion thruster. Thruster performance tests are conducted periodically over the entire NEXT throttle table with input power ranging 0.5 to 6.9 kW. Thruster performance parameters including thrust, input power, specific impulse, and thruster efficiency have been nominal with little variation to date. The NSTAR first-failure mode, accelerator aperture erosion leading to electron backstreaming, has been mitigated in the NEXT design. The severe NSTAR discharge cathode assembly erosion has been mitigated by a graphite keeper in the NEXT thruster. Tracking of the NEXT first failure mode, charge-exchange ion impingement on the accelerator grid causing hexagonal groove erosion, is consistent with model predictions and indicates thruster life greater than or equal to 750 kg throughput. This paper presents the status, performance data, and wear characteristics of the NEXT LDT to date.
Author
ION ENGINES; ION PROPULSION; ELECTROSTATICS; SPECIFIC IMPULSE; PERFORMANCE TESTS; TOTAL IMPULSE; SERVICE LIFE; POWER EFFICIENCY
20100002896 NASA Glenn Research Center, Cleveland, OH, United States
NEXT Long-Duration Test Neutralizer Performance and Erosion Characteristics
Herman, Daniel A.; Soulas, George C.; Patterson, Michael J.; December 2009; In English; 31st International Electric Propulsion Conference (IEPC 2009), 20-24 Sep. 2009, Ann Arbor, MI, United States; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 346620.04.08.02.02.01
Report No.(s): NASA/TM-2009-215838; IEPC-2009-154; E-17098; Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100002896
The NASA's Evolutionary Xenon Thruster (NEXT) program is developing the next-generation ion propulsion system with significant enhancements beyond the state-of-the-art to provide future NASA science missions with enhanced capabilities at a low total development cost. A Long-Duration Test (LDT) was initiated in June 2005, to verify the NEXT propellant throughput capability to a qualification-level of 450 kg, 1.5 times the anticipated throughput requirement of 300 kg per thruster based on mission analyses. As of September 2, 2009, the thruster has accumulated 24,400 hr of operation with extensive durations at the following input powers: 6.9, 4.7, 1.1, and 0.5 kW. The thruster has processed 434 kg of xenon, surpassing the NASA Solar Technology Application Readiness (NSTAR) program thruster propellant throughput demonstrated during the extended life testing of the Deep Space 1 flight spare ion thruster and approaching the NEXT development qualification throughput goal of 450 kg. The NEXT LDT has demonstrated a total impulse of 16.1 10(exp 6zzz0 N s; the highest total impulse ever demonstrated by an ion thruster. A reduction in neutralizer flow margin has been the only appreciable source of thruster performance degradation. The behavior of the neutralizer is not easily predicted due to both erosion and deposition observed in previous wear tests. Spot-to-plume mode transition flow data and in-situ erosion results for the LDT neutralizer are discussed. This loss of flow margin has been addressed through a combination of a design change in the prototype-model neutralizer to increase flow margin at low emission current and to update the NEXT throttle table to ensure adequate flow margin as a function of propellant throughput processed. The new throttle table will be used for future LDT operations. The performance of the NEXT LDT neutralizer is consistent with that observed for long-life hollow cathodes. The neutralizer life-limiting failure modes are progressing as expected and the neutralizer data indicate none of the neutralizer failures are imminent.
Author
ION ENGINES; ION PROPULSION; ELECTROSTATICS; ELECTRIC PROPULSION; XENON; WEAR TESTS; FAILURE MODES
Additions to the NASA Aeronautics and Space Database as of 02/08/2010
20100002998 NASA Glenn Research Center, Cleveland, OH, United States
Impact Testing on Reinforced Carbon-Carbon Flat Panels With BX-265 and PDL-1034 External Tank Foam for the Space Shuttle Return to Flight Program
Melis, Matthew E.; Revilock, Duane M.; Pereira, Michael J.; Lyle, Karen H.; December 2009; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 377816.06.03.02.04
Report No.(s): NASA/TM-2009-213642/REV1; E-15130; No Copyright; Avail.: CASI: A10, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100002998
Following the tragedy of the Orbiter Columbia (STS-107) on February 1, 2003, a major effort commenced to develop a better understanding of debris impacts and their effect on the space shuttle subsystems. An initiative to develop and validate physics-based computer models to predict damage from such impacts was a fundamental component of this effort. To develop the models it was necessary to physically characterize reinforced carbon-carbon (RCC) along with ice and foam debris materials, which could shed on ascent and impact the orbiter RCC leading edges. The validated models enabled the launch system community to use the impact analysis software LS-DYNA (Livermore Software Technology Corp.) to predict damage by potential and actual impact events on the orbiter leading edge and nose cap thermal protection systems. Validation of the material models was done through a three-level approach: Level 1-fundamental tests to obtain independent static and dynamic constitutive model properties of materials of interest, Level 2-subcomponent impact tests to provide highly controlled impact test data for the correlation and validation of the models, and Level 3-full-scale orbiter leading-edge impact tests to establish the final level of confidence for the analysis methodology. This report discusses the Level 2 test program conducted in the NASA Glenn Research Center (GRC) Ballistic Impact Laboratory with external tank foam impact tests on flat RCC panels, and presents the data observed. The Level 2 testing consisted of 54 impact tests in the NASA GRC Ballistic Impact Laboratory on 6- by 6-in. and 6- by 12-in. flat plates of RCC and evaluated two types of debris projectiles: BX-265 and PDL-1034 external tank foam. These impact tests helped determine the level of damage generated in the RCC flat plates by each projectile and validated the use of the foam and RCC models for use in LS-DYNA.
Author
CARBON-CARBON COMPOSITES; DYNAMIC MODELS; FOAMS; IMPACT DAMAGE; IMPACT TESTS; COLUMBIA (ORBITER); SPACE SHUTTLES
20100002999 NASA Glenn Research Center, Cleveland, OH, United States
Effects of Hypervelocity Impacts on Silicone Elastomer Seals and Mating Aluminum Surfaces
deGroh, Henry C., III; Steinetz, Bruce M.; December 2009; In English; 45th Joint Propulsion Conference and Exhibit, 2-8 Aug. 2009, Denver, CO, United States; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 644423.06.31.04.01.03.22
Report No.(s): NASA/TM-2009-215836; AIAA Paper 2009-5249; E-17051-1; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100002999
While in space silicone based elastomer seals planned for use on NASA's Crew Exploration Vehicle (CEV) are exposed to threats from micrometeoroids and orbital debris (MMOD). An understanding of these threats is required to assess risks to the crew, the CEV orbiter, and missions. An Earth based campaign of hypervelocity impacts on small scale seal rings has been done to help estimate MMOD threats to the primary docking seal being developed for the Low Impact Docking System (LIDS). LIDS is being developed to enable the CEV to dock to the ISS (International Space Station) or to Altair (NASA's next lunar lander). The silicone seal on LIDS seals against aluminum alloy flanges on ISS or Altair. Since the integrity of a seal depends on both sealing surfaces, aluminum targets were also impacted. The variables considered in this study included projectile mass, density, speed, incidence angle, seal materials, and target surface treatments and coatings. Most of the impacts used a velocity near 8 km/s and spherical aluminum projectiles (density = 2.7 g/cubic cm), however, a few tests were done near 5.6 km/s. Tests were also performed using projectile densities of 7.7, 2.79, 2.5 or 1.14 g/cubic cm. Projectile incidence angles examined included 0 deg, 45 deg, and 60 deg from normal to the plane of the target. Elastomer compounds impacted include Parker's S0383-70 and Esterline's ELA-SA-401 in the as received condition, or after an atomic oxygen treatment. Bare, anodized and nickel coated aluminum targets were tested simulating the candidate mating seal surface materials. After impact, seals and aluminum plates were leak tested: damaged seals were tested against an undamaged aluminum plate; and undamaged seals were placed at various locations over craters in aluminum plates. It has been shown that silicone elastomer seals can withstand an impressive level of damage before leaking beyond allowable limits. In general on the tests performed to date, the diameter of the crater in either the elastomer, or the aluminum, must be at least as big as 80% to 90% of width of the bulb of the seal before significant leakage occurs.
Author
ALUMINUM ALLOYS; ELASTOMERS; METAL PLATES; METAL SURFACES; SEALING; SILICONES; HYPERVELOCITY IMPACT; IMPACT DAMAGE; ALUMINUM
20100003003 NASA, Washington, DC, United States
Cosmos and Culture: Cultural Evolution in a Cosmic Context
Dick, Steven J., Editor; Lupisella, Mark L., Editor; 2009; In English; Original contains color and black and white illustrations
Report No.(s): NASA/SP-2009-4802; Copyright; Avail.: CASI: EA5, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100003003
This book is one of several on the societal impact of spaceflight in the NASA History Series, and is directly relevant to NASA s mandate to "provide for long-range studies of the potential benefits to be gained from, the opportu-nities for, and the problems involved in the utilization of aeronautical and space activities for peaceful and scientific purposes." Much of NASA s work may be seen as filling in the gaps in our knowledge of cosmic evolution. Perhaps the largest gap is the still very much open question of whether humans are alone in the universe, and what this means for humanity. We hope this book will stimu-late a more serious field of inquiry into how culture and cosmos relate based not only on how we understand our own cultural evolution, but on broader theo-retical grounds as well. It is only a first tentative step toward the scientific study of the relationship between cosmic and cultural evolution, of placing the rap-idly growing science of cultural evolution within a cosmic context, and urging a greater appreciation of the role that the cosmos should play in our culture. Topics covered include: Cosmic Evolution: State of the Science; Cosmic Evolution: History, Culture, and Human Destiny; Social Evolution: State of the Field; The Evolution of Culture; The Big Burp and the Multiplanetary Mandate; Evo Devo Universe?: A Framework for Speculations on Cosmic Culture; Dangerous Memes; or, What the Pandorans Let Loose; Cosmocultural Evolution: The Coevolution of Culture and Cosmos and the Creation of Cosmic Value; The Intelligent Universe; Life, Mind, and Culture as Fundamental Properties of the Universe; The Value of "L" and the Cosmic Bottleneck; Encoding Our Origins: Communicating the Evolutionary Epic in Interstellar Messages; History and Science after the Chronometric Revolution; Bringing Culture to Cosmos The Postbiological Universe; and Bringing Cosmos to Culture Harlow Shapley and the Uses of Cosmic Evolution.
Author
SPACE FLIGHT; UNIVERSE; COMMUNICATING; COSMOLOGY; EXTRATERRESTRIAL LIFE; ANTHROPOLOGY; GALAXIES; PLANETS; BIOLOGICAL EVOLUTION
20100003004 NASA, Washington, DC, United States
Evo Devo Universe? A Framework for Speculations on Cosmic Culture Chapter 6
Smart, John M.; Cosmos and Culture: Cultural Evolution in a Cosmic Context; 2009; pp. 291-29; In English; Original contains black and white illustrations
Copyright; Avail.: CASI: A05, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100003004
The underlying paradigm for cosmology is theoretical physics. In this paper we explore ways this framework might be extended with insights from information and computation studies and evolutionary developmental (evo-devo) biology. We also briefly consider implications of such a framework for cosmic culture. In organic systems, adaptive evolutionary development guides the production of intelligent, ordered, and complex structures. In such systems we can distinguish evolutionary processes that are stochastic, creative, and "divergent," and developmental processes that produce statistically predictable, robust, conservative, and "convergent" structures and trajectories. We will briefly model our universe as an evolutionary, information processing, and developmental system -- as an "evo compu devo" universe (abbreviated "evo devo" hereafter). Our framework will try to reconcile the majority of unpredictable, evolutionary features of universal emergence with a special subset of potentially statistically predictable and developmental universal trends, including: (1) accelerating advances in universal complexity (however we define such advances, e.g., Aunger 2007) seen over the last half of the universe s life history in contrast to deceleration during the first half (2) increasing spatial and temporal (space time) locality of universal complexity development (3) apparently hierarchical emergence of increasingly matter and energy efficient and matter and energy dense substrates (platforms) for adaptation and computation (4) apparent accelerating emergence, on Earth, of increasingly postbiological (technological) forms of intelligence, and their likely future trajectories. We use the phrase "evo devo" without the hyphen here to distinguish this speculative philosophy and systems theory from the legitimate science of "evo-devo" biology from which we seek insights.
Author
COSMOLOGY; INTELLIGENCE; UNIVERSE; EVOLUTION (DEVELOPMENT)
20100003005 NASA, Washington, DC, United States
Life, Mind, and Culture as Fundamental Properties of the Universe
Davies, Paul C. W.; Cosmos and Culture: Cultural Evolution in a Cosmic Context; 2009; pp. 383-39; In English; Original contains black and white illustrations
Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100003005
Traditionally, living systems have been regarded as a trivial and incidental embellishment to the physical world, of no particular significance in the over-all cosmic scheme of things. In this essay I shall argue that the orthodox view is profoundly wrong. Not only do I believe that life is a key part of the evolution of the universe, I maintain that mind and culture, too, will turn out to be of fundamental significance in the grand story of the cosmos.My argument has to appeal to indirect evidence, in view of the fact that Earth provides the only samples we currently know of life, mind, and culture. It is certainly possible that we are alone in the universe. If so, it does not necessarily mean that life is insignificant, even if it is confined at the moment to one planet. In principle, life and intelligence have the potential to spread across the cosmos from Earth, and given the immense duration of time available before the universe become depleted of useful sources of energy, there seems to be plenty of opportunity for our descendants to play a literally cosmic role.
Derived from text
COSMOLOGY; EVOLUTION (DEVELOPMENT); INTELLIGENCE; UNIVERSE
20100003006 NASA, Washington, DC, United States
Encoding Our Origins: Communicating the Evolutionary Epic in Interstellar Messages Chapter 12
Vakoch, Douglas A.; Cosmos and Culture: Cultural Evolution in a Cosmic Context; 2009; pp. 415-43; In English; Original contains black and white illustrations
Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100003006
Even before the first search for extraterrestrial intelligence (SETI) project was conducted, people have been pondering what reply we might send if some day we discover an extraterrestrial civilization. Some have suggested that the United Nations (U.N.) would be the international body of choice for deciding such a question, and indeed, that would seem one appropriate starting point. The challenge that the international SETI community has faced is gaining a space on the already full agenda of the U.N.; indeed, the preface to the existing SETI protocols endorsed by the International Academy of Astronautics (IAA) and the International Institute of Space Law explicitly acknowledges the difficulty of gaining the attention of the U.N. If some day we detect direct evidence of extraterrestrial intelligence, all that may well change, but what are we do to in the meantime? There is a natural alternative to the United Nations - a group whose discussions over the past decades already puts it in a position to recommend a coherent, consistent message that reflects broad-based, international consensus: the scientific community. To be clear, a solely scientific account of us would not capture the depth and breadth of human experience. For precisely that reason, over the past several years the IAA through its Interstellar Message Construction Study Group, in conjunction with the SETI Institute, has organized a series of workshops and conferences bringing together scholars from a range of disciplines - including the arts, music, humanities, theology, and law - aimed at identifying some of the many voices that should be represented in a comprehensive reply from Earth.
Author
EXTRATERRESTRIAL INTELLIGENCE; COMMUNICATING; IDENTIFYING; INTERNATIONAL LAW; MESSAGES; SPACE LAW
20100003007 NASA, Washington, DC, United States
The Evolution of Culture Chapter 4
Dennett, Daniel C.; Cosmos and Culture: Cultural Evolution in a Cosmic Context; 2009; pp. 125-14
Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100003007
Cultures evolve. In one sense, this is a truism; in other senses, it asserts one or another controversial, speculative, unconfirmed theory of culture. Consider a cultural inventory of some culture at some time - say 1900 AD. It should include all the languages, practices, ceremonies, edifices, methods, tools, myths, music, art, and so forth that compose that culture. Over time, that inventory changes. Today, 100 years later, some items will have disappeared, some multiplied, some merged, some changed, and many new elements will appear for the first time. A verbatim record of this changing inventory through history would not be science; it would be a database. This is the truism: cultures evolve over time. Everybody agrees about that. Now let s turn to the controversial question: how are we to explain the patterns to be found in that data-base? Are there any good theories or models of cultural evolution?
Author
SENSORY PERCEPTION; LANGUAGES; MUSIC; INVENTORIES; CULTURE (SOCIAL SCIENCES)
20100003008 NASA, Washington, DC, United States
The Big Burp and the Multiplanetary Mandate Chapter 5
Bloom, Howard; Cosmos and Culture: Cultural Evolution in a Cosmic Context; 2009; pp. 145-20; In English
Copyright; Avail.: CASI: A04, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100003008
Evolution is shouting a message at us. Yes, evolution herself. That imperative? Get your ass off this planet. Get your asses, your burros, your donkeys, and as many of your fellow species as you can - from bacteria and plants to fish, reptiles, and mammals - off this dangerous scrap of stone and find new niches for life. Take the Grand Experiment of Cells and DNA, the 3.85-bil-lion-year Project of Biomass, to other planets, moons, orbiting habitats, and galaxies. Give life an opportunity to thrive, to reinvent itself, to turn every old disaster, every pinwheeling galaxy, into new opportunity. Do this as the only species nature has generated that s capable of deliberate travel beyond the atmosphere of Earth. Do it as the only species able to take on the mission of making life multiplanetary. Accept that mission - the Greening of the Universe - or you may well eliminate yourself and all the species that depend on you - from the microorganisms making folic acid and vitamin K in your gut to wheat, corn, cucumbers, chickens, cows, the yeast you cultivate to make beer, and even the bacteria you use to make cheese. What s worse, if you fail to take life beyond the skies, the whole experiment of life - including rain-forests, whales, and endangered species - may die in some perfectly normal cosmic catastrophe.Where does this imperative to pierce the sky and to fly beyond the well of Earth s gravity come from? What does it have to do with the role of culture in the cosmos? And, most important, how does the relationship between culture and the cosmos tell us that space is a key to our future, a key to our evolutionary obligations, and a key to our ecological destiny? Let s start with a basic question whose answer may come as a surprise. What is culture and when did it begin? Culture is the multigenerational hard-drive of memory, change, and innovation. Culture transforms a record of the past into a prediction of the future; it transforms memory into tradition - into rules of how to proceed. And culture is profoundly social. It exists not just in one mind, but binds together mobs of minds in a common enterprise. When did culture first appear in this 13.73-billion-year-old universe? The answer is surprising. Most evolutionary experts say that human culture kicked off 35,000 to 45,000 years ago. Paleontologists studying prehistoric Europe call this period The Cultural Explosion.1 Thirty-five thousand to forty-five thousand years ago,2 men and women began to perforate, grind, polish, and drill bone, ivory, antler, shell, and stone into harpoons, fishhooks, buttons, ornaments, sewing needles, and awls.3 Frosting the cake, humans also invented musical instruments,4 calendars marked on pieces of antler,5 and paintings on the walls of caves.6 Then there s the un-standard answer about culture s beginnings, a rebel timeline of human culture that a relatively new paleoanthropological school is fighting for. This new scientific movement has made its digs in Africa, not Europe,7 and has come up with radically different dates. Culture, says this upstart school, started approximately 280,000 years ago8 when humans invented the makeup industry,9 then followed that with the invention of jewelry, beads, and trade.
Author
EARTH ATMOSPHERE; MICROORGANISMS; PLANETS; HUMAN BEINGS; HABITATS; ENDANGERED SPECIES; BACTERIA; BIOMASS; DEOXYRIBONUCLEIC ACID
20100003009 NASA, Washington, DC, United States
Cosmic Evolution: State of the Science Chapter 1
Chaisson, Eric J.; Cosmos and Culture: Cultural Evolution in a Cosmic Context; 2009; pp. 3-2; In English; Original contains color illustrations
Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100003009
Evolution, broadly considered, has become a powerful unifying concept in all of science, providing a comprehensive worldview for the new millennium. Among all of nature?s diverse systems, energy -- acquired, stored, and expressed --is a principal driver of the rising complexity of galaxies, stars, planets and life-forms in the expanding universe. Our cultural curiosity is both a result of, and a key to understanding, myriad cosmic-evolutionary events that have shaped our material origins.
Author
COSMOLOGY; GALACTIC EVOLUTION; UNIVERSE
20100003010 NASA, Washington, DC, United States
Cosmic Evolution: History, Culture, and Human Destiny Chapter 2
Dick, Steven J.; Cosmos and Culture: Cultural Evolution in a Cosmic Context; 2009; pp. 25-5; In English; Original contains color illustrations
Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100003010
During the course of the 20th century, a powerful new idea gradually entered human consciousness and culture: that we are part of a cosmos billions of years old and billions of light years in extent; that all parts of this cosmos are interconnected and evolving; and that the stories of our galaxy, our solar system, our planet, and ourselves are part and parcel of the ultimate master narrative of the universe, a story we now collectively term 'Cosmic evolution." Even as in some quarters of popular culture, heated debate continues over Darwinian evolution 150 years after the idea was published, over the last 50 years the much more encompassing idea that Carl Sagan embodied in the phrase "the cosmic connection" has become more and more a part of our daily lives, and will even more in the future as our cosmic consciousness increases. Cosmic evolution provides the proper universal context for biological evolution, revealing that the latter is only a small part of the bigger picture, in which everything is evolving, including life and culture. The more we know about science, the more we know culture and cosmos are connected, to such an extent that we can now see that the cosmos is inextricably intertwined with human destiny, both in the short term and the long-term, impinging on (and arguably essential to) questions normally reserved for religion and philosophy. It is the purpose of this chapter to uncover the historical evolution of this new understanding of the cosmos, describe the effects on culture so far, and outline the potentially far-reaching impact on the future of humanity.
Author
CONSCIOUSNESS; HISTORIES; UNIVERSE; COSMOLOGY
20100003011 NASA, Washington, DC, United States
History and Science after the Chronometric Revolution Chapter 13
Christian, David; Cosmos and Culture: Cultural Evolution in a Cosmic Context; 2009; pp. 441-46; In English
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Avail Online: http://hdl.handle.net/2060/20100003011
This paper describes a transformation in our understanding of the past, a transformation whose full significance has not yet been adequately appreciated. The transformation is associated with a revolution in the techniques used to date past events. I will argue that this "chronometric revolution," which occurred in the middle of the 20th century, has large implications for our understanding of both history, and of the relationship between history and science.The first part of this essay reviews the changing relationship between history and the sciences in the western world over several centuries. The second part describes the "chronometric revolution." The discipline of history has been transformed by two great chronometric revolutions. One occurred several millennia ago, after the appearance of writing. Written records made it possible, for the first time, to assign absolute dates to events many generations in the past. The second revolution occurred soon after the Second World War. It allowed us to assign reliable absolute dates to events extending back to the very origins of the universe. The third part explores some of the consequences of the chronometric revolution. By expanding our vision of the past to eras well before the appearance of our own species, the chronometric revolution historicized disciplines such as cosmology, geology, and biology and brought them closer in their methodologies to the discipline of history. The fourth part argues that the idea of increasing complexity offers a powerful thematic link between this newly discovered cluster of historically oriented disciplines. Over 13 billion years, increasingly complex entities have appeared in the universe, and modern human society may be one of the most complex of all these entities. Finally, the expanded vision of the past made possible by the chronometric revolution raises important questions about the distinctive nature of human history. I will argue that our species is distinguished by two complementary "emergent" properties. The first is an exceptional ability to adapt to different environments. The second is a unique capacity for seeking and finding "meaning." As a species we have a quite exceptional ability to keep finding new ways of adapting to our environments. I will argue that the source of this ability is "collective learning" -- the ability, unique to our species, to share learned information with precision and in great volume. That ability in turn is linked to our propensity for finding "meaning" through the sharing of symbols. In the light of these arguments, I will suggest that the expanded past revealed by the chronometric revolution allows us to redefine our sense of the past in general and of human history in particular.
Author
UNIVERSE; HISTORIES; INTELLIGENCE; EVOLUTION (DEVELOPMENT)
20100003012 NASA, Washington, DC, United States
Bringing Culture to Cosmos The Postbiological Universe Chapter 14
Dick, Steven J.; Cosmos and Culture: Cultural Evolution in a Cosmic Context; 2009; pp. 463-48; In English; Original contains black and white illustrations
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Avail Online: http://hdl.handle.net/2060/20100003012
The Biological Universe (Dick 1996) analyzed the history of the extraterrestrial life debate, documenting how scientists have assessed the chances of life beyond Earth during the 20th century. Here I propose another option - that we may in fact live in a postbiological universe, one that has evolved beyond flesh and blood intelligence to artificial intelligence (AI) that is a product of cultural rather than biological evolution. MacGowan and Ordway (1966), Davies (1995), and Shostak (1998), among others, have broached the subject, but the argument has not been given the attention it is due, nor has it been carried to its logical conclusion. This paper argues for the necessity of long-term thinking when contemplating the problem of intelligence in the universe. It provides arguments for a postbiological universe based on the likely age and lifetimes of technological civilizations and the overriding importance of cultural evolution as an element of cosmic evolution. And it describes the general nature of a postbiological universe and its implications for SETI.
Author
BIOLOGICAL EVOLUTION; INTELLIGENCE; ARTIFICIAL INTELLIGENCE; BLOOD
20100003013 NASA, Washington, DC, United States
Bringing Cosmos to Culture Harlow Shapley and the Uses of Cosmic Evolution Chapter 15
Palmeri, JoAnn; Cosmos and Culture: Cultural Evolution in a Cosmic Context; 2009; pp. 489-52; In English
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Avail Online: http://hdl.handle.net/2060/20100003013
The focus of this chapter is, on Harlow Shapley. The questions posed are biographical and historical. For example: How and why did Shapley come to identify cosmic evolution as the "greatest theme I know" and use it as a foundation for his vision of science and its ultimate significance for society? How and why did he come to promote his evolutionary perspective as "stellar theology" and "rational religion" in the postwar decades? More generally, how are Shapley s efforts to promote his message of "Life, Hope, and Cosmic Evolution" to be understood within the broader context of a life and career that spanned the great cultural, political, and scientific transformations of the 20th century? To answer these questions we must begin with an examination of Shapley s attempts to connect cosmos and culture in the early decades of the 20th century.
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BIOGRAPHY; HISTORIES; COSMOLOGY
20100003014 NASA, Washington, DC, United States
Dangerous Memes; or, What the Pandorans Let Loose Chapter 7
Blackmore, Susan; Cosmos and Culture: Cultural Evolution in a Cosmic Context; 2009; pp. 297-31; In English
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Avail Online: http://hdl.handle.net/2060/20100003014
Cultural evolution is a dangerous child for any species to let loose on its world. And the parent species, whatever it is like and wherever it arises, will have no insight into what it has done until its offspring is already grown and making its way in the world. By then it is too late to take it back. So I shall call this motherly species "Pandoran," after the mythical first Greek woman whose box released all the evils of mankind. We humans are Earth s Pandorans, and have let loose cultural evolution; but on other planets quite different creatures might be playing this role. Opening such a box of tricks can even be lethal, and I suspect that there are several danger points. The first critical step occurs when one species becomes capable of behavioral imitation, or of some other process that makes copying with variation and selection possible. This creates a new replicator, making the evolution of culture inevitable. This is the first danger point, because the newly created culture - the spreading of copied behaviors and the competition to mix, match, and make more - can get out of hand. Some of the behaviors may be so extravagant, or expensive, or dangerous, that they kill off their Pandorans and so obliterate themselves as well. This kind of waste is all part of how evolution works. Indeed natural selection might be called "design by death" because of all the billions of creations that have to die in spawning innovation and success for a few. If this first danger point is passed, the Pandorans and their newly spawned culture may begin to adapt to each other, and co-evolve towards a more symbiotic relationship, as diseases and their hosts sometimes do. If this succeeds, the result may be a stable mutualism that lasts indefinitely. Alternatively, with enough time and under the right conditions, another step might be taken. That is, new mechanisms for copying, varying, and selecting information could evolve outside of the Pandorans themselves, leading to a second danger point. For example, here on Earth, humans invented printing, sound recording and photography, vast communication networks, broadcasting, and the Internet. These are all methods of selective copying, which means a new evolutionary step and this creates a second danger point. As the copying increases, the thirst for innovation that s unleashed can be a drain not only on the Pandorans who started it but on their whole environment as well. This is what has happened here on Earth, with the consequent overpopulation and technological explosion threatening the health and climate of the entire planet. This danger point could be safely passed, or it might prove fatal. We don t yet know what the outcome will be here on Earth; it could go either way. However, our sample of one planet does at least allow us to think about the general picture and speculate about what might happen on other planets elsewhere in the cosmos. I like to imagine a vast universe containing many planets which have conditions suitable for life to evolve. On some of those planets a species evolves that is capable of copying what others do, thus unleashing this second evolutionary process. Among those planets, some survive the danger point and some do not, with the successful ones going on to spawn further evolutionary steps and face further danger points. On this picture, what should we expect to see around us? I would like to explore what might be out there on the basis of this memetic way of thinking about cultural evolution. I shall first explain a little about memes, meme theory, and the importance of replicators, and then consider some of the possible fates of planets that give birth to multiple replicators as ours has done.
Author
CULTURE (SOCIAL SCIENCES); COMMUNICATION NETWORKS; BROADCASTING; COMPETITION; HAZARDS; PLANETS; CREATIVITY; EXPLOSIONS
20100003015 NASA, Washington, DC, United States
Cosmocultural Evolution: The Coevolution of Culture and Cosmos and the Creation of Cosmic Value Chapter 8
Lupisella, Mark L.; Cosmos and Culture: Cultural Evolution in a Cosmic Context; 2009; pp. 321-35; In English; Original contains color illustrations
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Avail Online: http://hdl.handle.net/2060/20100003015
Culture is something special. It has helped life on Earth, particularly Homo sapiens, survive and thrive in ways that sometimes defies belief. What human beings have created, what we are becoming, is utterly remarkable, inspiring, mind-blowing. But is it an illusion of sorts? Is culture merely an increasingly complex result of biologically driven self-interest, arising from the happen-stance of life? Is it merely a blind walk (or run?) of replicating memes - the cultural equivalent of natural selection?1While it may be true that much, if not all, culture might ultimately be explained directly and indirectly by Darwinian explanations of one sort or another, it may also be true that cultural evolution is beginning to break free of our biological heritage. Natural selection has been working on the experiment of life for close to 4 billion years on Earth, and what we witness now with human culture is so rich, so complex, so uncertain, that we have to wonder how it will evolve, and how it may be evolving elsewhere in the universe.Other species on Earth arguably exhibit basic forms of culture, but those instances appear to be far less complex, and perhaps far less meaningful than what human beings experience. Our technology, art, and what we know of our world, is unspeakably exhilarating and terrifyingly dangerous. We are capable of powerful creations and complete annihilation. Our consciousness is uncontainable - to the point of agonizing awareness. Homo sapiens sapiens has a power unlike Earth has ever seen. To some, this anthropocentric cheerleading will seem the worst sort of "speciesism" - a kind of blind, unethical delusion engendered by biologically driven affinities for one s own likeness. But exaltation of humanity in no way justifies unchecked devotion at the expense of others who inhabit our world and perhaps worlds beyond. Nevertheless, the evidence seems clear: human beings are running away with culture. And it may be running away with us. We get the prize - the Culture Prize. We deserve it. We've worked hard, made untold sacrifices. We are smart in a way no other animal is. And through us, if not others, the Culture Prize is bestowed upon the Cosmos. It is in this context that I hope to 1) provide a basic framework for thinking about how culture and cosmos might relate - the primary notion being "cosmocultural evolution" and/or the Cosmocultural Principle; 2) briefly develop the notion of "bootstrapped cosmocultural evolution," including practical near- and longer-term implications; 3) suggest a long-term worldview, consistent with 1 and 2, that can be characterized as a morally creative cultural cosmos - a post-intelligent, post-technological universe that enters the realm of conscious evolution driven largely by moral and creative pursuits
Author
CONSCIOUSNESS; CULTURE (SOCIAL SCIENCES); HUMAN BEINGS; LIFE SCIENCES; ILLUSIONS; CREATIVITY; ANNIHILATION REACTIONS
20100003016 NASA, Washington, DC, United States
The Value of "L" and the Cosmic Bottleneck Chapter 11
Shostak, Seth; Cosmos and Culture: Cultural Evolution in a Cosmic Context; 2009; pp. 399-41; In English; Original contains black and white illustrations
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Avail Online: http://hdl.handle.net/2060/20100003016
The Drake Equation, a commonly used starting point for discussions about the likelihood of finding extraterrestrial intelligence, is now nearly a half-century old. It dates from 1961, a year after Frank Drake made his pioneering radio search for artificial signals from other worlds. That search, dubbed "Project Ozma," was a 200-hour scrutiny of two nearby, Sun-like stars for transmissions spectrally situated near the 1420 MHz line of neutral hydrogen, and was conducted with an 85-foot-antenna at the National Radio Astronomy Observatory in Green Bank, West Virginia (Kellermann and Seielstad 1985; Drake 1960). These efforts to find easy evidence of intelligence in other star systems provoked considerable public interest, including a major article in the Saturday Review (Lear 1960).As a sequel, Drake organized a two-day conference a year later on searching for sentience in the galaxy - the so-called Green Bank Conference. The invitees comprised approximately 10 astronomers, biologists, and technical specialists. As a conference agenda, Drake composed a simple, linear equation (Drake 1965) for estimating the number of galactic civilizations that are sending signals we could detect. The last term in this famous formula is L, the lifetime of a signaling society. L is sui generis among the equation s factors for two reasons: 1. It is dependent on sociology, not astronomy or biology (the only other term that is similar in this regard is f(sub c), the fraction of intelligent species that develop a technical civilization).2. It is arguably the term that we know, and perhaps can know, least about. At a conference in 1971, Carl Sagan noted that in trying to evaluate the terms of the Drake Equation "We are faced . . . with very difficult problems of extrapolating from, in some cases, only one example and in the case of L, from no examples at all. When we make estimates we cannot pretend that these values are reliable." (Sagan 1973). This is a daunting caveat. It has not, however, squelched speculation on the value of L. The fact that these estimates are speculative can be gauged by the degree to which they differ. In a compilation by Steven Dick, published estimates for L range over five orders of magnitude (Dick 1996). Clearly, the chances of finding a signal with SETI experiments depend strongly on the value of L. For example, if the invention of nuclear weapons is always nearly simultaneous with the development of radio and laser technology (as is the case for Homo sapiens), then it is seductive to argue that when a species is technically mature enough to make its presence known from afar, it is also ripe for effecting its own destruction. In that case, L might be only a few centuries or less, and the opportunity for intercepting a signal is very limited. Having some inkling of what L might be - even if that estimate has an uncertainty of a magnitude or two - is significant in motivating (or perhaps demoralizing) those seeking evidence of intelligence elsewhere.The other reason for considering the value of L, quite independent of SETI, is that as a matter of self-interest, it s clearly of consequence to know if our species - or at least our culture - can reasonably hope for a long future.
Author
RADIO SIGNALS; RADIO ASTRONOMY; LASER APPLICATIONS; MICROWAVE SPECTRA; EXTRATERRESTRIAL INTELLIGENCE; SOCIOLOGY; EXTRAPOLATION
20100003017 NASA, Washington, DC, United States
The Intelligent Universe Chapter 9
Gardner, James; Cosmos and Culture: Cultural Evolution in a Cosmic Context; 2009; pp. 361-38; In English
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Avail Online: http://hdl.handle.net/2060/20100003017
Some thoughtful observers are beginning to focus on an portentous possibility: that we may be approaching a kind of cultural tipping point, after which human history as we currently know it will be superseded by hypervelocity cultural evolution driven by transhuman computer intelligence. If this prospect is realistic, then a key task may be to not only comprehend the ideas that are currently driving historical trends but also to attempt to actually shape them -- to launch an exercise in what I have previously called memetic engineering -- aimed at ensuring that the better angels of our nature prevail in the strange new transhuman cultural environment that may lie just over history?s frontier.This essay will suggest that the emergence of a novel scientific worldview that places life and intelligence at the center of the vast, seemingly impersonal physical processes of the cosmos may offer the best hope for meeting this uniquely daunting challenge. The concept of an intelligent universe may turn out to be the key tool with which memetic engineers will build the cultural foundation for a benign cosmic future in which human beings no longer play the dominant role.
Author
INTELLIGENCE; UNIVERSE
20100003018 NASA, Washington, DC, United States
Social Evolution: State of the Field Chapter 3
Denning, Kathryn; Cosmos and Culture: Cultural Evolution in a Cosmic Context; 2009; pp. 63-12; In English
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Avail Online: http://hdl.handle.net/2060/20100003018
Placing Earth into the largest possible context is easier in some ways than others. High school students can identify the place of our Sun in the typology of stars. We know our solar system's mailing address within our galaxy, and how to find our galaxy within the local group neighborhood. We can study our home world's geology and atmosphere objectively, and classify Earth appropriately in the ever-growing list of extrasolar planets. Our knowledge of other stars, galaxies, and planets changes, but we have observed external realities in relation to which we can locate ourselves. It becomes more difficult when we discuss life, because, at the time of writing, none of any kind has been discovered elsewhere. We are, for the moment, still positioning Earth s life in relation to ideas - rumored phantoms which have yet to materialize in our view, no matter how logically likely they might be. So, when we discuss intelligent life-forms with technological societies in the absolute absence of extraterrestrial cases, we are philosophically and scientifically adrift. We can mark Earth s physical coordinates on the galactic map, and we can find our star and planet in tables and typologies, but we cannot, in any way, position human civilization in relation to any other technological civilization. And yet, while we wait for data about extraterrestrial intelligence with which to anchor ourselves, we muse about our place in the cosmos. We bold sketch our hypothetical neighbors, debate how we might find them, guess what they might be thinking and doing, and wonder what we should say to them. These speculations are driven simultaneously by our knowledge of their potential neighborhoods (planetary systems and habitable zones), and our knowledge of ourselves (our own planet, its biota, and societies). With respect to imagining life and civilizations elsewhere, we are, therefore, caught between logics that tug in different directions and do not easily mesh. This poses significant challenges. For example, the processes of working downwards from generalities about the universe, and working upwards from the particularities of Earth, promote competing perspectives about our place in the cosmos. Few thinkers can effectively balance both. The balancing act requires scholars from the humanities and social sciences to expand their horizons and wonder whether we can simultaneously be intelligent agents determining our own futures, dwelling in historical time with all its contingencies, and part of much larger patterns with knowable rules and predictable outcomes. It also requires scholars primarily trained in the physical sciences to take a closer look at Earth s societies to develop the most nuanced understanding possible of the data and theory we have at our disposal and to consider how, exactly, knowledge of our own case might relate to other cases. In this chapter, I attempt to facilitate the latter task by providing an overview of some of the most difficult, contentious, and promising areas in social evolution research, as pertinent to culture in the cosmos. The modern literature about social evolution runs many disciplines wide and several centuries deep; so this is necessarily a selective review, shaped by my own perspective that is rooted in anthropology, biological anthropology, archaeology, and the history and philosophy of science. Much of the chapter addresses background issues relevant to the general problem of integrating social evolution on Earth into syntheses about cosmic evolution and to the particular problem of SETI (the Search for Extraterrestrial Intelligence). I begin with some essential preliminaries about social evolution and SETI the data, competing epistemologies, why social evolution matters, motivations for studying social change, and disciplinary differences. The challenges of researching social evolution are best illustrated in context, so I then provide an extended case study which examines approaches to the perennially fasciting subject of collapse. In the remaining sections, I briefly review the current status of selected relevant debates in the method and theory of social evolutionary studies including the relationship of biology and culture, a new Modern Synthesis/Holistic Darwinism, complexity theory, hologeistic studies, interactions between civilizations, the roles of contingency and convergence, and the lifetimes of civilizations. I conclude that there are many promising routes forward. The blossoming of new theoretical perspectives which accommodate complex systems, the development of improved tools for studying the history of societies on Earth, and our increased awareness of our own subjectivities in these studies will enable ever-better investigations of how civilizations develop, interact, and expire or endure.
Author
PLANETARY SYSTEMS; GALAXIES; EXTRASOLAR PLANETS; SOLAR SYSTEM; HABITABILITY; EARTH (PLANET); PHYSICAL SCIENCES; ANTHROPOLOGY; GEOLOGY
Additions to the NASA Aeronautics and Space Database as of 02/09/2010
20100003052 NASA Langley Research Center, Hampton, VA, United States
Sizing Single Cantilever Beam Specimens for Characterizing Facesheet/Core Peel Debonding in Sandwich Structure
Ratcliffe, James G.; January 2010; In English; Original contains color and black and white illustrations
Contract(s)/Grant(s): WBS 814358.02.01.07
Report No.(s): NASA/TP-2010-216169; LF99-10031; L-19806; No Copyright; Avail.: CASI: A03, Hardcopy
Avail Online: http://hdl.handle.net/2060/20100003052
This technical publication details part of an effort focused on the development of a standardized facesheet/core peel debonding test procedure. The purpose of the test is to characterize facesheet/core peel in sandwich structure, accomplished through the measurement of the critical strain energy release rate associated with the debonding process. Following an examination of previously developed tests and a recent evaluation of a selection of these methods, a single cantilever beam (SCB) specimen was identified as being a promising candidate for establishing such a standardized test procedure. The objective of the work described here was to begin development of a protocol for conducting a SCB test that will render the procedure suitable for standardization. To this end, a sizing methodology was developed to ensure appropriate SCB specimen dimensions are selected for a given sandwich system. Application of this method to actual sandwich systems yielded SCB specimen dimensions that would be practical for use. This study resulted in the development of a practical SCB specimen sizing method, which should be well-suited for incorporation into a standardized testing protocol.
Author
DEBONDING (MATERIALS); SANDWICH STRUCTURES; STRAIN MEASUREMENT; STRAIN ENERGY RELEASE RATE; CANTILEVER BEAMS
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