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arXiv · 1710.08044

Inf-sup stable finite elements on barycentric refinements producing divergence--free approximations in arbitrary dimensions

Johnny Guzman·Michael Neilan
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Abstract

We construct several stable finite element pairs for the Stokes problem on barycentric refinements in arbitrary dimensions. A key feature of the spaces is that the divergence maps the discrete velocity space onto the the discrete pressure space; thus, when applied to models of incompressible flows, the pairs yield divergence-free velocity approximations. The key result is a local inf-sup stability that holds for any dimension and for any polynomial degree. With this result, we construct global divergence-free and stable pairs in arbitrary dimension and for any polynomial degree.

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Johnny Guzman, Michael Neilan. 2017-10-23. Inf-sup stable finite elements on barycentric refinements producing divergence--free approximations in arbitrary dimensions. https://arxiv.org/abs/1710.08044

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