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arXiv · 1902.01218

First-order continuous- and discontinuous-Galerkin moment models for a linear kinetic equation: model derivation and realizability theory

Florian Schneider·Tobias Leibner
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Abstract

We provide two new classes of moment models for linear kinetic equations in slab and three-dimensional geometry. They are based on classical finite elements and low-order discontinuous-Galerkin approximations on the unit sphere. We investigate their realizability conditions and other basic properties. Numerical tests show that these models are more efficient than classical full-moment models in a space-homogeneous test, when the analytical solution is not smooth.

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Florian Schneider, Tobias Leibner. 2019-02-01. First-order continuous- and discontinuous-Galerkin moment models for a linear kinetic equation: model derivation and realizability theory. https://doi.org/10.1016/j.jcp.2020.109547

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