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The dance of a flame in the microgravity
of space, reducing the roar of aircraft engines, and spearheading
novel concepts that may make interstellar travel a reality one
day are among the research fields being pursued at the NASA Glenn
Research Center at Lewis Field in Cleveland, Ohio.
In March 1999, the Lewis Research Center was officially renamed
the NASA John H. Glenn Research Center at Lewis Field, in recognition
of America's first astronaut to orbit the Earth and his four
terms of senatorial work on behalf of Ohio and the nation in
the U.S. Congress. George William Lewis was the research director
for the National Advisory Committee for Aeronautics, the predecessor
to NASA.
"The blending of names reflects the pioneering research
in aerospace technology that employees have performed throughout
the center's history and will continue to perform in the future,"
observes Glenn's director, Donald J. Campbell.
Power, propulsion, and communications technologies are high-priority
research domains being advanced at the center, so that U.S. leadership
in these areas is ensured. Since the early formative years of
the space agency, work in turbomachinery at Glenn has been underway.
Glenn's turbomachinery research goals are focused on technology
that enables aircraft engine manufacturers to design advanced
turbine engines. This research has included the development of
new high-temperature materials, coatings, and lubrication systems;
development and verification of design, modeling, and computational
codes for workstation computers and visualization tools; basic
research in flow physics and heat transfer; and combustion research.
All of this work has been supported by materials testing, component
testing, and prototype testing in facilities that simulate operating
conditions of turbomachinery.
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The effect of microgravity on combustion
processes has been a major area of research guided by Glenn Research
Center scientists. Knowledge about the physics of combustion
may lead to more efficient combustion of materials, and therefore
a savings of fuel. |
Along with the U.S. aeropropulsion industry, Glenn is enabling
technology for the next generation of subsonic gas turbine engines,
which are environmentally friendly, fuel efficient, durable,
and globally-marketable. For example, Glenn engineers are taking
the technological steps to reduce nitrous oxide emissions--prime
contributors to the development of smog--from gas turbine engines.
Experimental and analytical work is also being performed in three
areas of engine noise reduction: active noise control for fans,
advanced low-noise fan designs, and jet noise.
In the field of general aviation, Glenn's advanced subsonic
technology work is striving to improve the safety, performance,
and ease-of-use of general aviation aircraft. Efforts at the
center include advanced propulsion sensors and controls to allow
simplified intermittent combustion engine and aircraft control
rather than the approach taken over the last 40 years. Gains
are being made in civil tilt rotor aircraft, too. While this
subsonic aircraft can take off and land using less runway and
appears viable in relieving air traffic congestion, Glenn experts
are tackling noise, terminal-area operations, safety, weight
reduction, and reliability issues.
High above Earth, the Advanced Communications Technology Satellite
(ACTS) is trailblazing advanced communication technologies and
services. Released into orbit by a Space Shuttle crew in 1993,
the ACTS symbolizes Glenn's long history of developing state-of-the-art
communications technology. The center has formed partnerships
with industry, universities, and other government agencies to
utilize the Ka-band spectrum through ACTS, to validate use of
all-digital, high-bandwidth, on-demand, integrated multimedia
services.

| An array of microphones
inside the Aero-Acoustic Propulsion Laboratory at the Glenn Research
Center measures simulated aircraft engine noise during takeoffs.
Acoustic data collected is used to certify aircraft engines,
as specified by the Federal Aviation Administration (FAA). |
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Work in ion propulsion
technology at Glenn Research Center made possible the technology
validation flight of the Deep Space 1 spacecraft. The fuel-efficient
ion engine was tested in space in 1998-1999, and is to be utilized
on 21st century deep space missions. |
A major milestone in propulsion technology is the in-space
shakeout of the ion engine aboard NASA's Deep Space 1, launched
in late 1998. Glenn engineers have long been working on ion engines,
technology that produces an almost imperceptible thrust that
is equivalent to the pressure exerted by a sheet of paper held
in the palm of a hand. While the xenon-fueled ion engine is slow
to pick up speed, over the long haul it can deliver 10 times
as much thrust per pound of fuel as liquid or solid fuel rockets.
Ion drives are likely to be used on future deep space and Earth-orbiting
missions that would otherwise be impractical or unaffordable
with conventional propulsion systems.
Glenn's Fluids and Combustion Facility for the International
Space Station is a modular, multi-user facility accommodating
microgravity science experiments. In the absence of gravity,
combustion takes place in a very different manner than on Earth.
Gravity plays a role in why flames behave the way they do, smoke
rises, and how large air circulation currents are established.
These effects can mask the physical processes of combustion.
Understanding what exactly is happening in the physics of combustion
is sure to have major payoffs. Combustion powers our automobiles,
generates our electricity, heats our homes, even cooks our food
on the back-yard grill, and adds many pollutants to our skies.
Microgravity research in this area aboard the Space Station could
offer ways of increasing combustion efficiency, thus reducing
pollution, global warming, and production and transportation
costs.
Taking a long view into the 21st century, current
work at Glenn is studying futuristic propulsion concepts. Ultimate
breakthroughs in space transportation are under review at the
center involving propelling a vehicle without propellant mass,
attaining the maximum transit speeds physically possible, and
creating new energy production methods to power such devices.
Nobody can predict where insights into these areas may take future
robotic and human explorers.
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