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arXiv · 2112.15153

DPG methods for a fourth-order div problem

Thomas Führer·Pablo Herrera·Norbert Heuer
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Abstract

We study a fourth-order div problem and its approximation by the discontinuous Petrov-Galerkin method with optimal test functions. We present two variants, based on first and second-order systems. In both cases we prove well-posedness of the formulation and quasi-optimal convergence of the approximation. Our analysis includes the fully-discrete schemes with approximated test functions, for general dimension and polynomial degree in the first-order case, and for two dimensions and lowest-order approximation in the second-order case. Numerical results illustrate the performance for quasi-uniform and adaptively refined meshes.

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Thomas Führer, Pablo Herrera, Norbert Heuer. 2021-12-30. DPG methods for a fourth-order div problem. https://arxiv.org/abs/2112.15153

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