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arXiv · 2402.06493

Sparse-grid Discontinuous Galerkin Methods for the Vlasov-Poisson-Lenard-Bernstein Model

Stefan Schnake·Coleman Kendrick·Eirik Endeve·Miroslav Stoyanov·Steven Hahn·Cory D Hauck·David L Green·Phil Snyder·John Canik
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Abstract

Sparse-grid methods have recently gained interest in reducing the computational cost of solving high-dimensional kinetic equations. In this paper, we construct adaptive and hybrid sparse-grid methods for the Vlasov-Poisson-Lenard-Bernstein (VPLB) model. This model has applications to plasma physics and is simulated in two reduced geometries: a 0x3v space homogeneous geometry and a 1x3v slab geometry. We use the discontinuous Galerkin (DG) method as a base discretization due to its high-order accuracy and ability to preserve important structural properties of partial differential equations. We utilize a multiwavelet basis expansion to determine the sparse-grid basis and the adaptive mesh criteria. We analyze the proposed sparse-grid methods on a suite of three test problems by computing the savings afforded by sparse-grids in comparison to standard solutions of the DG method. The results are obtained using the adaptive sparse-grid discretization library ASGarD.

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Stefan Schnake, Coleman Kendrick, Eirik Endeve, Miroslav Stoyanov, Steven Hahn, Cory D Hauck, David L Green, Phil Snyder, John Canik. 2024-02-09. Sparse-grid Discontinuous Galerkin Methods for the Vlasov-Poisson-Lenard-Bernstein Model. https://arxiv.org/abs/2402.06493

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