Michael Mewhinney

NASA Ames Research Center, Moffett Field, CA

(Phone: 650/604-3937, 650/604-9000)

mmewhinney@mail.arc.nasa.gov

RELEASE: 00-30

NOTE TO EDITORS AND NEWS DIRECTORS: As part of Earth Day activities at NASA
Ames Research Center, Moffett Field, CA, news media are invited to
photograph a research wind turbine and interview test engineers in the
world’s largest wind tunnel on Thursday, April 20, 2000, from 10:30 a.m. to
12:30 p.m. PDT. To get to Ames, take the Moffett Field exit off Highway
101. At the Moffett Federal Airfield main gate, proceed to the Visitor
Badging Office to obtain entry badges and maps to the 80-by-120-foot wind
tunnel. Bring press credentials and photo ID to gain admittance.

For the first time ever, engineers at NASA’s Ames Research Center,
located in California’s Silicon Valley, are testing a wind turbine in the
world’s largest wind tunnel to learn how to design and operate the turbines
more efficiently.

The three-week test of the U.S. Department of Energy’s National
Renewable Energy Laboratory (NREL) “Unsteady Aerodynamics” research wind
turbine began on April 17 and will conclude May 5. Tests will be conducted
in Ames’ 80-by-120-Foot Wind Tunnel. The wind tunnel is primarily used for
determining low- and medium-speed aerodynamic characteristics of full-scale
aircraft and rotorcraft (helicopters).

“Some of the problems encountered by wind turbines are very similar to
those experienced by rotorcraft,” explained Bob Kufeld, NASA project
director. “NREL and NASA are working together using our wind tunnel and
helicopter computer models that predict rotorcraft characteristics and
their research wind turbine model to learn as much as possible about
rotating blade aerodynamics,” he said.

“If we can better understand the aerodynamics of rotating blades, then
we can more accurately predict how the wind turbines will behave,” said
Dave Simms, NREL project director. “Our organization conducts research to
make wind turbines operate more efficiently, more cheaply and more
effectively,” he added. “This research will help us learn how to build
better turbines.”

The research wind turbine is designed to measure structural loads and
aerodynamic responses of the rotating blade or wing. The research wind
turbine is mainly constructed from steel, but has lightweight carbon-fiber
blades that measure 33 feet (10 meters) in diameter. The system weighs
about 15,000 pounds (6,800 kilograms). Wind turbines, such as those found
on the Altamont Pass in the East Bay (east of the San Francisco Bay, CA)
are used to generate electricity for commercial uses.

During the wind tunnel test, the turbine will be mounted on a 40-foot tall
stand and operated at a constant speed with its rotor turned left or right
at various angles and different wind velocities. The wind tunnel is
capable of producing wind speeds up to 115 miles per hour. NREL engineers
developed the test objectives to meet recommendations of an international
science panel of wind-turbine aerodynamics experts.

The NREL research turbine has been field-tested in various
configurations since 1989 at the Department of Energy’s National Wind
Technology Center located near Boulder, CO. The turbine has been operated
in outdoor atmospheric turbulent wind conditions up to 70 mph, and has been
exposed to winds above 145 mph with the rotor locked in position. Test
data have shown that turbulent winds create complex operating environments
for wind turbines.

According to Simms, testing in a controlled wind-tunnel environment
will eliminate these factors, and produce valuable data that will enable
researchers to better understand how the turbines operate at various angles
and wind speeds. “We need data to improve and validate enhanced
engineering models for designing and analyzing advanced wind-energy
machines,” Simms said. “Hopefully, this test will provide that data.”

Note to Broadcast News Media: NASA Television will broadcast b-roll of the
research wind turbine in the wind tunnel, footage of wind turbines at
Altamont Pass and interviews with project engineers on Thursday, April 20.
The video airs at 9 a.m. 12 Noon, 3 p.m., 6 p.m. and 9 p.m. All times PDT
and are subject to change. Check NASA website: http://www.nasa.gov/ntv/
NTV is broadcast on GE-2, transponder 9C, C-Band, located at 85 degrees
West longitude. The frequency is 3880.0 MHz. Polarization is vertical and
audio is monaural at 6.8 MHz.