SEARCH · Search NASA
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Fast acting gas valve is used for injecting a short pulse of gas into a vacuum chamber during plasma acceleration experiments. It contains a lightweight closure disk that is forced away from the valve seat when an electromagnetic coil is momentarily energized and immediately rebounds from a stop back onto the seat.
Two methods of starting the Brayton power system have been considered: (1) using the alternator as a motor to spin the Brayton rotating unit (BRU), and (2) spinning the BRU by forced gas injection. The first method requires the use of an auxiliary electrical power source. An alternating voltage is applied to the terminals of the alternator to drive it as an induction motor. Only gas-injection starts are discussed in this report. The gas-injection starting method requires high-pressure gas storage and valves to route the gas flow to provide correct BRU rotation. An analog computer simulation was used to size hardware and to determine safe start and shutdown procedures. The simulation was also used to define the range of conditions for successful startups. Experimental data were also obtained under various test conditions. These data verify the validity of the start and shutdown procedures.
Gas-injection cone in fluidized-bed reactor for coating particles with silicon or carbon cooled and protected from abrasion by stream of gas flowing over surface of cone. Hot particles entering reaction zone are coated with silicon or carbon supplied by thermal decomposition of suitable gas injected into reaction zone.
We discuss the formation of an artificial atmosphere generated by vigorous lunar base activity in this paper. We developed an analytical, steady-state model for a lunar atmosphere based upon previous investigations of the Moon's atmosphere from Apollo. Constant gas-injection rates, ballistic trajectories, and a Maxwellian particle distribution for an oxygen-like gas are assumed. Even for the extreme case of continuous He-3 mining of the lunar regolith, we find that the lunar atmosphere would not significantly degrade astronomical observations beyond about 10 km from the mining operation.