Simulation of multi-species kinetic instabilities with the Numerical Flow Iteration

Abstract

Kinetic instabilities are one of the most challenging aspects in computational plasma physics. Accurately capturing their onset and evolution requires fine resolution of the high-dimensional distribution functions of each relevant species, which quickly becomes computationally prohibitively expensive. Additionally, plasma dynamics is an inherently multi-scale phenomenon due to the vast separation of scales between heavy ions and light-weight electrons. In previous work the Numerical Flow Iteration (NuFI) was suggested as a high-fidelity alternative with reduced memory complexity making it an interesting candidate to simulate complicated kinetic instabilities. In this work we extend NuFI to non-periodic boundary conditions and demonstrate how it is possible to reduce the computational complexity to allow for longer simulation periods.