2-D Modeling of Orificed Hollow Cathodes of Stationary Plasma Thrusters SPT-100

Abstract

In this paper, 2-D extended fluid model for the simulation of orificed hollow cathode (OHC) discharge in xenon flow of SPT-100 thruster was built using Comsol Multiphysics. Self-consistent discharge model is based on fluid description of ions and excited neutral species and uses drift-diffusion approximation for the particle fluxes. Electron transport and rates of electron-induced plasma-chemical reactions are calculated using Boltzmann equation for electron energy distribution function and corresponding collision cross sections. A reasonable set of plasma-chemical processes with electrons, ions, and excited and neutral particles were considered. The model accounts for gas flow and heating. Self-consistent electric field is calculated from the Poisson equation. The model geometry reproduces that of the experimental OHC for stationary plasma thruster SPT-100, which was studied in Harbin Institute of Technology. Simulations were carried out for different operational modes of the OHC. Distributions of key discharge parameters were obtained. A comparison between the simulation results and experimental data was conducted and showed good agreement.