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arXiv · 2404.18549

High Fidelity simulations of the multi-species Vlasov equation in the electro-static, collisional-less limit

Rostislav-Paul Wilhelm·Jan Eifert·Manuel Torrilhon
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Abstract

The accurate prediction of occurrence and strength of kinetic instabilities in plasmas remains a significant challenge in nuclear fusion research. To accurately capture the plasmas dynamics one is required to solve the Vlasov equation for several species which, however, comes with a number of challenges as high dimensionality of the model as well as turbulence and development of fine but relevant structures in the distribution function. The predominantly employed Particle-in-Cell (PIC) method often lacks the accuracy to resolve the dynamics correctly, which can only be remedied by going to higher resolutions but at a prohibitorily high cost due to the high-dimensionality. Thus in this work we discuss the usage of the Numerical Flow Iteration (NuFI) as high fidelity approach, in contrast to e.g. PIC or grid-based approaches, to solve the multi-species Vlasov equation in modes leading to kinetic instabilities.

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Rostislav-Paul Wilhelm, Jan Eifert, Manuel Torrilhon. 2024-04-29. High Fidelity simulations of the multi-species Vlasov equation in the electro-static, collisional-less limit. https://arxiv.org/abs/2404.18549

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