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建立人际资源圈Magnetic_Levitation
2013-11-13 来源: 类别: 更多范文
Magnetic Levitation
In addition to rocket and air-breathing propulsion work involving combustion, NASA is beginning to test concepts such as magnetic levitation (MagLev) systems that could hurtle future reusable launch vehicles off their pads with ground-based electrical fields.
NASA MagLev testing is to enter a major new phase next spring. The use of a MagLev launch-assist track would reduce the vehicle size and propellant needed to place a payload in orbit. The work is underway at Marshall Space Flight Center and Lawrence Livermore National Laboratory.
By using a MagLev track to provide the initial 400-600 mph. of velocity at 2g of acceleration, engineers believe they could develop a winged space vehicle 20% smaller than one with a comparable payload using all self-contained propellant, said Sherry Buschmann, Marshall's project manager for Launch Technologies.
The advantage with MagLev is that propulsion for the initial acceleration off the runway is ground-based electricity that does not have to be carried by the flight vehicle.
Marshall engineers believe that a 1.5-mi. MagLev track could be used to accelerate a 120,000-150,000-lb. RLV about the size of an SR-71 using only $75 of electricity. The carriage for the flight vehicle would weigh 60,000 lb. and stay on the track at vehicle liftoff.
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