Splitting methods for Fourier spectral discretizations of the strongly magnetized Vlasov-Poisson and the Vlasov-Maxwell system

Jakob Ameres

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arXiv · 1907.05319

Splitting methods for Fourier spectral discretizations of the strongly magnetized Vlasov-Poisson and the Vlasov-Maxwell system

Jakob Ameres

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Abstract

Fourier spectral discretizations belong to the most straightforward methods for solving the unmagnetized Vlasov--Poisson system in low dimensions. In this article, this highly accurate approach is extended two the four-dimensional magnetized Vlasov--Poisson system with new splitting methods suited for strong magnetic fields. Consequently, a comparison to the asymptotic fluid model is provided at the example of a turbulent Kelvin--Helmholtz instability. For the three dimensional electromagnetic Vlasov--Maxwell system different novel charge conserving implementations of a Hamiltonian splitting are discussed and simulation results of the Weibel streaming instability are presented.

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Jakob Ameres. 2019-07-11. Splitting methods for Fourier spectral discretizations of the strongly magnetized Vlasov-Poisson and the Vlasov-Maxwell system. https://arxiv.org/abs/1907.05319

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