Modeling & Simulation I

Low-temperature plasmas (LTPs) can exhibit non-Maxwellian velocity distribution functions (VDFs) due to plasma-wall interactions, collisions, instabilities and magnetization. A high-fidelity fluid moment model that can capture the effects of non-Maxwellian VDFs would allow for more accurate predictions of transport and reaction rates in LTPs. Fluid moment models are an attractive option to model plasma devices because of their computational cost in comparison to kinetic models that need to track individual particle trajectories. Near absorbing walls, or when the plasma is magnetized, there can be strong temperature anisotropies in the plasma which are not captured by traditional LTP fluid models. This talk will focus on the development of a 10-moment fluid model, which is benchmarked with a 5-moment fluid model and kinetic simulations, to study anisotropic temperatures in plasma devices. We employ an electrostatic 10-moment model in one and two spatial dimensions to study instabilities and modified transport in an E×B discharge, approximating the geometry of a Hall-effect thruster. We have also developed electromagnetic 10-moment model that uses the non-relativistic Darwin approximation to study induced magnetic fields in partially magnetized plasmas.

Funding acknowledgement

This work was supported by the U.S. Department of Energy National Nuclear Security Administration Stewardship Science Graduate Fellowship under cooperative agreement DE-NA0003960.