Steady-state plasma model of an iodine-fueled Hall thruster

Abstract

A time-independent, one-dimensional plasma model is proposed and used to investigate the characteristics and performance of iodine-fueled Hall thrusters. The model accounts for radial plasma-wall losses and includes major iodine collisional reaction processes such as molecular dissociation. Thruster performance is found to be comparable to that obtained with xenon, although iodine allows extension of the operating range to lower mass flow rates and discharge voltages. The model predicts an appreciable fraction of molecular ions (I2+) within the thruster plume that depends on the discharge voltage and propellant mass flow rate and that contributes significantly to the thrust. In contrast to xenon, electron impact dissociation of iodine leads to the unique formation of two distinct ionization zones within the thruster: a region closer to the anode associated with the ionization of molecular iodine and a downstream region associated with the ionization of atomic iodine.