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arXiv · 2407.09626

Conservative Closures of the Vlasov-Poisson Equations Based on Symmetrically Weighted Hermite Spectral Expansion

Opal Issan·Oleksandr Koshkarov·Federico D. Halpern·Boris Kramer·Gian Luca Delzanno
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Abstract

We derive conservative closures of the Vlasov-Poisson equations discretized in velocity via the symmetrically weighted Hermite spectral expansion. The short note analyzes the conservative closures preservation of the hyperbolicity and anti-symmetry of the Vlasov equation. Furthermore, we verify numerically the analytically derived conservative closures on simulating a classic electrostatic benchmark problem: the Langmuir wave. The numerical results and analytic analysis show that the closure by truncation is the most suitable conservative closure for the symmetrically weighted Hermite formulation.

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Opal Issan, Oleksandr Koshkarov, Federico D. Halpern, Boris Kramer, Gian Luca Delzanno. 2024-07-12. Conservative Closures of the Vlasov-Poisson Equations Based on Symmetrically Weighted Hermite Spectral Expansion. https://arxiv.org/abs/2407.09626

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