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arXiv · 2208.00941

Stabilizing discontinuous Galerkin methods using Dafermos' entropy rate criterion

Simon-Christian Klein
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Abstract

A novel approach for the stabilization of the discontinuous Galerkin method based on the Dafermos entropy rate crition is presented. The approach is centered around the efficient solution of linear or nonlinear optimization problems in every timestep as a correction to the basic discontinuous Galerkin scheme. The thereby enforced Dafermos criterion results in improved stability compared to the basic method while retaining the order of the method in numerical experiments. Further modification of the optimization problem allows also to enforce classical entropy inequalities for the scheme. The proposed stabilization is therefore an alternative to flux-differencing, finite-volume subcells, artificial viscosity, modal filtering, and other shock capturing procedures.

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Simon-Christian Klein. 2022-08-01. Stabilizing discontinuous Galerkin methods using Dafermos' entropy rate criterion. https://arxiv.org/abs/2208.00941

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