Modeling of a Pulsed Plasma Thruster from Plasma Generation to Plume Far Field

Models are presented for a Teflon-fed, pulsed plasma thruster from plasma generation to plume far field. A one-dimensional model using local thermodynamic equilibrium is developed to describe the plasma generation, Teflon ablation, and nozzle acceleration processes. A computer code that uses two different particle methods is employed to simulate the unsteady plasma plume expansion processes, including charge exchange collisions. Results are generated for a pulsed plasma thruster under development at the University of Illinois. General features of the plume reveal substantial differences in the expansion dynamics of the charged and neutral species. In addition, there is a noticeable difference between the behavior of the carbon and the fluorine ions. Direct comparisons are made between simulation results and experimentally measured data for electron number density and plasma potential. These comparisons indicate strengths and weaknesses of the models.