Three-dimensional numerical simulation of the plasma plume from a stationary plasma thruster

A numerical method is proposed for simulating the low-density plasma plume exhausted from a stationary plasma thruster in a three-dimensional setting. In contrast to the axisymmetric approximation, the problem is formulated so as to determine the effect of the backflow on the upstream region and the thruster walls, which are of finite size. The numerical method is a generalization of rarefied gas numerical methods to the case when the force field is not specified analytically. The method takes into account the delta-function character of the boundary ion distribution function and the considerable difference between the velocity scales of ions and neutral atoms, which transform into each other. Numerical results are presented that demonstrate the effect of some factors on the plasma plume.