Comparison of Low Earth Orbit Wake Current Collection Simulations Using Nascap-2k, SPIS, and MUSCAT Computer Codes

The structure of the wake generated by an object immersed in a dense, low temperature, drifting plasma is simulated using three different spacecraft charging software tools, Nascap-2k, the Spacecraft Plasma Interaction Software (SPIS), and the Multi-Utility Spacecraft Charging Analysis Tool (MUSCAT). Each tool uses different algorithms to simulate the particle dynamics, the space charge effect on the electric field, and the currents collected by the object. The system modeled is a plate with a high negative potential on the wake side. The results from the different simulations agree with each other and with experiments conducted on the same configuration. In particular, the nontrivial shape of the collected current density map is correctly simulated by all the codes. The comparison illustrates the strengths of the various approaches.