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arXiv · 2105.10409

A divergence-free finite element method for the Stokes problem with boundary correction

Haoran Liu·Michael Neilan·Baris Otus
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Abstract

This paper constructs and analyzes a boundary correction finite element method for the Stokes problem based on the Scott-Vogelius pair on Clough-Tocher splits. The velocity space consists of continuous piecewise quadratic polynomials, and the pressure space consists of piecewise linear polynomials without continuity constraints. A Lagrange multiplier space that consists of continuous piecewise quadratic polynomials with respect to boundary partition is introduced to enforce boundary conditions as well as to mitigate the lack of pressure-robustness. We prove several inf-sup conditions, leading to the well-posedness of the method. In addition, we show that the method converges with optimal order and the velocity approximation is divergence free.

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Haoran Liu, Michael Neilan, Baris Otus. 2021-05-21. A divergence-free finite element method for the Stokes problem with boundary correction. https://arxiv.org/abs/2105.10409

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