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arXiv · 2505.18321

A structure-preserving local discontinuous Galerkin method for the Fokker-Planck-Landau equation

Kun Huang·Andrés Galindo-Olarte·Rodrigo González-Hernández·Irene M. Gamba
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Abstract

In this work, we introduce a structure-preserving local discontinuous Galerkin (LDG) method \cite{cockburn1998local} for solving the non-local non-linear Fokker-Planck-Landau (FPL) equations. We rephrase the structure-preserving strategy of Shiroto and Sentoku\cite{shiroto2019structure} in the language of numerical analysis, and extend it to the LDG framework. We propose a method that is not only conservative, but also stabilized through upwind flux. The apparent contradiction between conservation laws and numerical stabilization is elegantly resolved by leveraging the properties of the jump terms inherent to the LDG framework. In the numerical experiments, our scheme is tested with benchmark examples.

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Kun Huang, Andrés Galindo-Olarte, Rodrigo González-Hernández, Irene M. Gamba. 2025-05-23. A structure-preserving local discontinuous Galerkin method for the Fokker-Planck-Landau equation. https://arxiv.org/abs/2505.18321

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