A quasi-conservative dynamical low-rank algorithm for the Vlasov equation

Lukas Einkemmer; Christian Lubich

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arXiv · 1807.02338

A quasi-conservative dynamical low-rank algorithm for the Vlasov equation

Lukas Einkemmer·Christian Lubich

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Abstract

Numerical methods that approximate the solution of the Vlasov-Poisson equation by a low-rank representation have been considered recently. These methods can be extremely effective from a computational point of view, but contrary to most Eulerian Vlasov solvers, they do not conserve mass and momentum, neither globally nor in respecting the corresponding local conservation laws. This can be a significant limitation for intermediate and long time integration. In this paper we propose a numerical algorithm that overcomes some of these difficulties and demonstrate its utility by presenting numerical simulations.

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Lukas Einkemmer, Christian Lubich. 2018-07-06. A quasi-conservative dynamical low-rank algorithm for the Vlasov equation. https://arxiv.org/abs/1807.02338

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