Yesterday’s meeting of the Northeast Ohio Software Association (NEOSA) included a great tour of NASA Glenn Research Center (GRC). We saw three facilities, none of which I had toured before. First stop was the Propulsion Systems Laboratory (PSL), which is used to test jet engines. Glenn Research Center has long provided services to jet engine manufacturers in developing and testing engines for both commercial and military planes. The PSL includes two test chambers that can simulate flight at altitude conditions–low pressure and low temperature–while collecting data from inside and outside the engine. It is not an easy task simulating altitudes up to 90000 ft., mach 4 speed, and -90 degrees F inlet conditions, with a running jet engine in the chamber. One upcoming program will examine engine icing, which is believed to have been responsible for more than 250 engine flameouts. It is believed that ice forms on aircraft parts and enters the engine, where it melts in the compressor. The liquid water extinguishes the flames in the burner, causing the engine to shut down.
The second stop on the tour was the Electric Propulsion Laboratory. Electric propulsion, or ionic propulsion, is used mainly on satellites and deep space probes. Instead of a chemical rocket propellant, ionic propulsion systems use ionized atoms–typically xenon atoms–as propellants. The ions are accelerated through an electric field and then escape from the engine. The high rate of acceleration results in strong thrust without using a lot of propellant, which allows lighter weight and/or longer missions than can be achieved with chemical fuels. The engines only work in the vacuum of space, though, so once again a large facility was needed to pump air out of the test chamber and simulate high altitudes. A cryo pump is used in order to simulate the nearly total vacuum of space. Most of the air is removed using mechanical pumps, but the remaining few particles are removed by chilling them to almost absolute zero. At such low temperatures the air atoms have almost no energy and simply collect on the liquid-helium-chilled cryo pump surface.
The final stop on the tour was the Research Analysis Center, with its 3D and virtual reality computer facilities. These systems are used by engineers to get an immersive experience visualizing images from space, flow simulations, engineering structures, and anything else where a three-dimensional display is useful, including finding new ways of presenting data. NASA engineers have worked with medical professionals also, who are excited about the possibilities for immersive visualizing of MRIs and other medical images. The lab is also a popular spot among children on school tours. Our guide admitted, though, that with falling prices for games and other entertainment, it was getting harder and harder to show the children things they had not already seen.
A reception followed the tour with delicious refreshments and a chance to meet astronaut Michael Foreman, who has flown on two Space Shuttle missions and is now chief of external programs for GRC.