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

Rostislav-Paul Wilhelm; Manuel Torrilhon

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arXiv · 2511.02405

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

Rostislav-Paul Wilhelm·Manuel Torrilhon

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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.

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Rostislav-Paul Wilhelm, Manuel Torrilhon. 2025-11-04. Simulation of multi-species kinetic instabilities with the Numerical Flow Iteration. https://arxiv.org/abs/2511.02405

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