PARAMETRIC STUDIES OF THE HALL CURRENT PLASMA THRUSTER

The Hall current plasma thruster accelerates a plasma jet by an axial electric field and an applied radial magnetic field in an annular cera mic channel. A relatively large current density (>0.1 A/cm(2)) can be obtained as the acceleration mechanism is not limited by space charge effects. Such a device can be used as a small rocket engine on board s pacecraft with the advantage of a large jet velocity compared to conve ntional rocket engines (10000-30000 m/s versus 2000-4800 m/s). An expe rimental Half thruster was constructed and operated in a broad range b f operating conditions and under various configuration variations. Ele ctrical, magnetic and plasma diagnostics, and as well accurate thrust and gas flow rate measurements, have been used to investigate the depe ndence of thruster behavior on the applied voltage, gas flow rate, mag netic field, channel geometry and wall material. The studies conducted so far have demonstrated a significant effect of channel material on thruster electrical characteristics and the existence of an optimal ch annel length for a given flow rate. Representative results highlightin g these findings are presented. (C) 1998 American Institute of Physics .