Three-dimensional particle simulation of the plume of a pulsed plasma thruster

The plume characteristics of a pulsed plasma thruster (PPT) are considered necessary in the evaluation of plume/spacecraft interactions. In this article, the rarefied plasma plume of a laboratory PPT is characterized. First, a three-dimensional (3D) physical model with boundary conditions is presented. Then, the particle-in-cell and direct simulation Monte-Carlo hybrid methods are employed to study the flow field. The profiles of the plasma density and potential and their variations versus time are analysed. Also, the computational results are compared with experiment data as well as with results from existing two-dimensional (2D) simulations. The comparisons show that the computational model can predict the electron density of plume in both parallel and perpendicular planes. It is also shown that the 3D predictions are more accurate than those of the 2D model. Analysis of the plume backflow indicates that less than one thousandth of the mass that is released from the solid propellant enters the backflow region at the end of a pulse period.