Segmented electrode hall thruster

Thrust, thrust efficiency, and plume divergence were measured for a 9 cm diam laboratory model Hall thruster with segmented electrodes in the discharge channel. Several geometries with graphite nonemissive electrodes, and one with a tungsten emissive electrode were tested and compared to a baseline configuration with all electrodes replaced by boron nitride segments. To within measurement uncertainty, thrust and thrust efficiency were unaffected by insertion of electrodes, with the exception of reduced efficiency for a configuration which resulted in a 20% increase in discharge current. Maximum plume half-angle reductions of 4 deg were obtained with emissive and nonemissive electrodes.