Numerical Simulation of the Cathode Plume of a Hall Thruster

Abstract

The plasma plume generated by the cathode of a 6-kW laboratory Hall thruster is modeled using a hybrid particle-fluid method. The approach utilizes the direct simulation Monte Carlo method to simulate the collision dynamics of heavy particles, the particle-in-cell method to model the transport of heavy species including the effects of electrostatic fields on the ions, and a “fluid” method that solves conservation equations to compute electron properties. Two previous internal plasma simulations for a hollow cathode and discharge plasmas are utilized as input boundary conditions to the full plume simulation in this study. The simulation results are assessed through comparison with various experimental data. Since the current model neglects the magnetic fields, the effect of mapping the thruster inlet onto a magnetic field line outside the strongest regions is employed to mitigate the effect of magnetic field, which in turn results in more accurate prediction when compared with experimental data.