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Glenn Research Center, located
on the outskirts of Cleveland, Ohio, is dedicated to creating
technologies that will propel us into the new millennium. Perhaps
it is this, as well as a dedication to innovation and excellence,
that has positioned Glenn a NASA's Center of Excellence in turbomachinery.
This attitude and sense of pride is exemplified in the ongoing,
cutting-edge activities being conducted at the Center.
The Glenn-managed Ultra-Efficient
Engine Technology (UEET) Program includes participation from
Ames Research Center, Langley Research Center, and Goddard Space
Flight Center, as well as five engine and two airplane manufacturers.
The six-year, nearly $300 million program's goal is to demonstrate
new engine technologies that reduce aircraft emissions, reduce
noise, and increase performance. Much of the success will come
from improved materials, new propulsion controls, advanced combustors,
and turbomachinery concepts. This technology is in the works,
with the integration of technologies in a working engine, while
integrating the engine into an aircraft airframe is still to
come. The UEET Program will enable future-generation aircraft
to travel a wide range of flight speeds, farther, cleaner, and
safer than ever before.
In 2000, Glenn completed the
hardware development of its Physics of Colloids in Space experiment.
The experiment is one of a series of Glenn-managed microgravity
science experiments scheduled to be conducted on the International
Space Station (ISS). A colloid consists of fine, insoluble particles
suspended in a fluid. Everyday examples of colloids are paint,
milk, salad dressings, and aerosols. The Physics of Colloids
in Space experiment will allow scientists to study the basic
physical properties of colloids without the influence of gravity.
The long-term goal of this investigation is to learn how to steer
the growth of colloids to create new materials and structures.
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Glenn Research Center's sapphire
refractive secondary concentrator will be used with primary
collector-concentrators to focus solar energy. The solar energy
can be used in power conversion systems, thermal propulsion
systems, and solar furnaces. |
Glenn is
the co-lead for ISS's electrical power system with Johnson Space
Center. Glenn is responsible for the technical design and development
of all the individual pieces of the electrical power system on
ISS, and is the proud major provider of the electrical power
equipment for the ISS. Glenn technologies were carried to the
ISS aboard two Shuttle missions in 2000. STS-92, launched in
October 2000, carried the Integrated Truss Structure Z1, which
includes four pieces of the ISS's electrical power equipment,
all of which Glenn developed: the plasma contactor, a high-tech
grounding rod for ISS; converter units, which provide grounding
and voltage regulation; the remote power control modules, which
are multichannel high-power circuit breakers for both switching
and protection in case of a short circuit during ISS construction
activities; and circuit isolation devices, which are manually-activated
switches that provide manual shut-off of high power.
On STS-97 station assembly flight
4A in November 2000, the first U.S. photovoltaic (PV) module
was carried to the ISS and installed. The module supplies the
ISS with solar power via solar arrays, batteries, and other power
system electronics. Glenn had a significant role in the design
and development of the PV module and managed the hardware development
of the flight hardware. Also installed on that mission were two
radiators, which remove waste heat from ISS. One of these radiator
panels was tested in the Space Power Facility, the world's largest
space environment simulation chamber at Glenn's Plum Brook Station
in Sandusky, Ohio.
Common to many of the space applications
that use solar thermal energy--such as electric power conversion,
thermal propulsion, and furnaces--is a need for highly efficient,
solar concentration systems. An effort is underway at Glenn to
develop a refractive secondary concentrator, which uses refraction
and total internal reflection to efficiently concentrate and
direct solar energy. When used in combination with advanced lightweight
primary concentrators, the refractive secondary concentrator
will produce very high system concentration ratios (10,000 to
1) and, of more practical interest, very high temperatures (>2000
°K).
The innovative refractive secondary
concentrator has significant advantages over all other types
of secondary concentrators. It is very efficient, requires no
active cooling, relaxes the pointing and tracking requirements
of the primary concentrator, and enables very high system concentration
ratios. This technology can be used in any system that requires
the conversion of solar energy to heat, for example, materials
research furnaces on ISS and thermal propulsion systems.
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The Physics of Colloids in
Space hardware is now flying on the ISS and producing pictures
like the one above of the colloid with polymers experiment.
Scientists varied the amount of polymer in each mixture to
cause the suspension to act like fluid, glass, crystals, or
gels. |
Continuing
in its heritage of innovation, Glenn researchers have developed
a new alloy for use in regeneratively cooled rocket engines.
The GRCop-84 alloy has an excellent combination of conductivity,
thermal expansion, strength, creep resistance, ductility, and
low-cycle fatigue life. Its use is expected to enable significant
gains in engine performance and reliability. The ultimate test
was to actually use the new alloy as a liner and test it in a
rocket engine. Two 6-inch-long liners with inner diameters of
approximately 2 inches were fabricated at Marshall using a vacuum
plasma spraying technique, and then tested at Glenn. Twenty-seven
hot fire tests were conducted, after which the liners showed
no signs of degradation.
As part of NASA's Aviation Safety
Program goals to reduce aviation accidents due to icing, Glenn
is leading a flight simulator development activity to improve
pilot training for adverse flying characteristics due to icing.
Flight simulators that include the aerodynamic effects of icing
will give pilots realistic exposure to the effects of icing-induced
hazards, such as ice-contaminated roll upset, tailplane stall,
or other loss-of-control events that may result from ice on the
airframe.
In order to achieve a high fidelity
flight simulation, wind tunnel tests were conducted on a 6.5-percent-scale
model of a Twin Otter aircraft. These tests resulted in databases
containing aerodynamic forces and moments, as functions of angle
of attack; sideslip; control surface deflections; forced oscillations
in the pitch, roll, and yaw axes; and various rotational speeds.
Some wing and tail surface pressure data were also recorded.
The databases are the foundation for a PC-based Icing Flight
Simulator delivered to Glenn in fiscal year 2001.
The continued activities at Glenn
make the Center a shining example of the vast array of NASA's
benefits. Work conducted at Glenn Research Center helps to open
windows to new worlds of opportunity both in space and on Earth.
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