When NASA Ames runs its massive wind tunnels, the surrounding area knows it. Local aircraft are warned of potential updrafts. Electric utilities brace for sudden power draws. And nearby residents are said to hear its 300-knot airflows from miles away.
Thanks to the sponsorship of Littelfuse Inc., Design News recently had the opportunity to tour the facility, and it didn’t disappoint. The National Full-Scale Aerodynamics Complex, as it’s formally known, has to be experienced to be appreciated. Used primarily for aerodynamic and acoustic tests on rotorcraft and powered-lift aircraft, it’s also capable of doing full-scale tests on an F/A-18 supersonic fighter jet. The facility has even been the site of one-third scale tests on the Space Shuttle.
The power it needs to perform such tests is almost mind-boggling. Air is driven by six 40-ft-diameter, 15-bladed variable-pitch fans powered by 40-pole, 6,600V synchronous motors, each rated at 18,000 HP. To spin the wooden blades, each weighing 880 lb, the facility burns up to 104 MW.
”It’s equal to the energy usage of a city of 225,000 people,” William Warmbrodt, chief of aeromechanics for NASA Ames Research Center, told Design News. “It’s like we’ve introduced 225,000 people to the northern California utility grid.” Up until about 20 years ago, NASA Ames had to schedule its use of the 80 ft x 120 ft tunnel with Pacific Gas and Electric Co. for fear it would use up too much of the available power on hot, sunny days. Today, NASA owns 5.5 percent of northern California’s Shasta Dam, and gets its power from there, Warmbrodt told us.
All that power, however, goes to good use. By spinning the huge fans, the facility’s 40 ft x 80 ft wind tunnel tops out at an airspeed of 300 knots, while the larger, 80 ft x 120 ft wind tunnel hits 100 knots. NASA engineers use those powerful winds to investigate aerodynamics and validate computational methods. They also examine aeromechanical stability boundaries of advanced rotorcraft and determine dynamic characteristics of new aircraft configurations.
”This is a very good facility for doing full aerodynamic evaluation of large-scale models,” Warmbrodt said.
I agree, the video is well worth watching. It is an amazing facility and I thought it very interesting that NASA owns a percentages of Shasta Dam to supply its power needs - that is good financial management. It would be neat to see some video of it in action with actual test conditions...
I, too, was intrigued by the power usage, Bob. Our tour guide told us that they draw energy off the grid, not only from California, but from Oregon, Washington and Idaho, too. They also own 5.5% of the energy coming from Shasta Dam in northern California.
Very interesting. The power useage is impressive and makes me wonder how much excess capacity is built into the power grid to permit occasional use of that and similar power hungry industries and how many there are. I had wondered how they manage to move such a dramatic amount of air without ingesting the local flora and fauna. Nice article: Thanks.
I think of it in exactly the same way, naperlou. The Byron nuclear station, which serves more than two million homes in northern Illinois, has two reactors and a capacity of 2.3 GW. If you assume that the wind tunnel is using abouth 5% of that huge plant's capacity, it's a stunning figure.
Another way to look at the power consumption is to compare it to the standard nuclear power plant. In Illinois the individual reactors run between 875 and 1,165MW. So that would put the wind tunnel at a tenth of a nuclear reactor.
The question of whether engineers could have foreseen the shortcut maintenance procedures that led to the crash of American Airlines Flight 191 in 1979 will probably linger for as long as there is an engineering profession.
More than 35 years later, the post-mortem on one of the country’s worst engineering disasters appears to be simple. A contractor asked for a change in an original design. The change was approved by engineers, later resulting in a mammoth structural collapse that killed 114 people and injured 216 more.
If you’re an embedded systems engineer whose analog capabilities are getting a little bit rusty, then you’ll want to take note of an upcoming Design News Continuing Education Center class, “Analog Design for the Digital World,” running Monday, Nov. 17 through Friday, Nov. 21.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.