Implementation of a polytropic model for two-dimensional hybrid Hall thruster simulations

A polytropic model for Hall discharge simulations is developed and tested against data for a laboratory Hall thruster. 2-D hybrid particle-in-cell (PIC) simulations, widely used to describe plasma properties of Hall thrusters, solve the electron energy equation for electron temperature requiring electron mobility as a specified parameter. Motivated by experiments that suggest a simpler polytropic relation between the electron density and electron temperature, we have adopted a 2-D hybrid-PIC to use this relationship as a means of relaxing the need to specify the electron mobility. By removing the usual ad-hoc assumptions of the form of the electron mobility, the polytropic model, if transportable to other operating conditions and Hall thruster designs, can be a powerful performance estimator and optimization tool. In this presentation, we discuss the implementation of this model and early results.