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arXiv · 2404.12732

Stability, convergence, and pressure-robustness of numerical schemes for incompressible flows with hybrid velocity and pressure

Lorenzo Botti·Michele Botti·Daniele Antonio Di Pietro·Francesco Carlo Massa
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Abstract

In this work we study the stability, convergence, and pressure-robustness of discretization methods for incompressible flows with hybrid velocity and pressure. Specifically, focusing on the Stokes problem, we identify a set of assumptions that yield inf-sup stability as well as error estimates which distinguish the velocity- and pressure-related contributions to the error. We additionally identify the key properties under which the pressure-related contributions vanish in the estimate of the velocity, thus leading to pressure-robustness. Several examples of existing and new schemes that fit into the framework are provided, and extensive numerical validation of the theoretical properties is provided.

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Lorenzo Botti, Michele Botti, Daniele Antonio Di Pietro, Francesco Carlo Massa. 2024-04-19. Stability, convergence, and pressure-robustness of numerical schemes for incompressible flows with hybrid velocity and pressure. https://arxiv.org/abs/2404.12732

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