Title :
Microwave electrothermal propulsion for space
Author_Institution :
NASA Lewis Res. Center, Cleveland, OH, USA
fDate :
6/1/1992 12:00:00 AM
Abstract :
The microwave electrothermal thruster (MET) is attractive for medium- or high-power spacecraft propulsion. A propellant gas is heated by passing it through a microwave plasma discharge created in a resonant cavity by tuning either the TM(011) or the TM(012) mode for impedance-matched operation. The MET is electrodeless, synergistically combines high pressure and high power capability, provides external control over the energy-conversion discharge, and operates on hydrogen propellant. Upwards of 95% efficiency has been reported. Calculations of potential MET performance are reported. Apparatus for testing the MET to power levels of 30 kW at 915 MHz is described. The low-ripple operation of the microwave generator has been verified, as has a procedure for starting the microwave discharge and raising the power applied to the cavity. Impedance-matched resonant operation of the microwave cavity has been achieved
Keywords :
aerospace propulsion; cavity resonators; discharges (electric); space vehicles; 30 kW; 915 MHz; 95 percent; H2; MET; energy-conversion discharge; impedance-matched operation; impedance-matched resonant operation; low-ripple operation; microwave discharge; microwave electrothermal thruster; microwave plasma discharge; propellant gas; resonant cavity; spacecraft propulsion; Cogeneration; Electromagnetic heating; Electrothermal effects; Hydrogen; Impedance; Plasmas; Pressure control; Propulsion; Resonance; Space vehicles;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
