A theoretical investigation of a magnetically shielded Hall thruster with conducting walls

Abstract

A 5 kW-class, magnetically shielded Hall effect thruster made of conducting walls is analyzed with a 2D particle/fluid model, in an attempt to understand the trends observed in recent prototypes. Two electrical configurations are considered: floating lateral walls and anode-tied lateral walls. The plasma response in both scenarios is compared with the baseline case of ceramic lateral walls. Under the same operating conditions and magnetic topology, there are minimal changes in performance and in most of the bulk plasma properties for the three cases. The main differences are observed in the electron current and energy flows to the walls in the anode-tied configuration, where the back wall receives only one fourth of the discharge current, and the energy deposition is more uniformly distributed along the walls, as compared with the other two cases, representing a potential advantage from the thermal management perspective. In a subsequent study on the anode-tied configuration, increasing the injected mass flow, up to a factor of four, reduces the energy losses per particle at the wall. At high mass flow operation, there is a large presence of doubly charged ions in the near plume, and the discharge power increases more than proportionally with the injected mass flow, but the thrust efficiency remains invariant.