Comparison of Methods for Numerical Modeling of Electric Propulsion Plume-Spacecraft Interaction
Masters Thesis Presentation by Rikard Siljeströmer
Time: Fri 2022-01-21 14.00 - 15.00
Participating: Rikard Siljeströmer
This project aims to compare the results from plume-spacecraft interaction using different numerical plasma simulation methods, with thruster data from COMAT Plasma-JetPack Vacuum Arc Thruster. The report summarizes and assesses the differences of using software with different numerical methods, SPIS (Spacecraft Plasma Interaction Software) using a heavy PIC (Particle-In-Cell) algorithm modeling the physical behavior of thruster particles, and oPEP (openPlumeEP), using a Ray-Tracing algorithm modeling the reduction of the physical properties using the inverse square principle according to standard physics. A numerical model and mesh were created in the GMSH environment based on OHB Sweden’s InnoSat platform. Using this mesh, numerous simulations were performed in both software with added measuring instruments and surfaces. Calibration of the simulation was done using the SPT100. Underlining approximations and assumptions are explained in the report.
Results from simulations suggest what was initially believed; close to the vicinity of the thruster exhaust both models produce similar results since the flow is undisturbed and experience what is believed to be laminar flow. Further away from the exhausts the results differ with SPIS under-estimating as opposed to oPEP. The main reason for this is believed to be that further out the plume flow is disturbed by internal/external forces reacting with the particles creating vortices, which oPEP does not capture in the Ray-Tracing algorithm unlike SPIS with its PIC algorithm.