Initial Use of a 3-D Plasma Simulation System for Predicting Surface Sputtering and Contamination by Hall Thrusters

Abstract : A 3-D Plasma Interaction Modeling System is being developed to predict the interaction of electric propulsion plumes with surfaces. The system, named COLISEUM, is designed to be flexible, usable, and expandable, allowing users to define surfaces with their choice of off-the-shelf 3-D solid modeling packages. These surfaces are then loaded into COLISEUM, which performs plasma operations based on user commands. Functional modules are interchangeable, and can range from simple (prescribed plume field) to complex (PIC-DSMC). Surface interaction parameters such as ion flux, ion energy, sputtering, and re-deposition are computed. Development to date has progressed to include the two simplest functional modules: prescribed_plume, which imports and superimposes a plume distribution, and ray, which performs ray tracing of flux from point sources. More sophisticated functional plasma simulation modules such as PIC-Hybrid-MCC are currently being integrated. This paper presents some of the first COLISEUM results--sputtering and re-deposition predictions on a spacecraft and in a vacuum chamber due to operation of Hall-effect thrusters.