Impact of discharge chamber geometry on characteristics of a low-power Hall thruster

A 200 W permanent-magnet Hall thruster - named PPI for “Petit Propulseur Innovant” - has been operated with xenon for three values of the channel width. The mean channel diameter, the channel length and the magnetic field topology stay fixed. Series of experiments have been carried out for each geometry over a broad set of propellant mass flow rates and applied voltages to investigate the impact of a channel width variation on discharge properties. The ion current was measured in the plume far field by means of a planar Faraday probe. The equilibrium temperature of inner and outer Al₂O₃ channel walls was determined by means of calibrated thermal imaging. Finally, the ion velocity was measured by laser-induced fluorescence spectroscopy at 834 nm along the channel centerline.