A Pressure-Robust Weak Galerkin Finite Element Method for Navier-Stokes Equations

Lin Mu

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arXiv · 2011.11526

A Pressure-Robust Weak Galerkin Finite Element Method for Navier-Stokes Equations

Lin Mu

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Abstract

In this paper, we develop and analyze a novel numerical scheme for the steady incompressible Navier-Stokes equations by the weak Galerkin methods. The divergence-preserving velocity reconstruction operator is employed in the discretization of momentum equation. By employing the velocity construction operator, our algorithm can achieve pressure-robust, which means, the velocity error is independent of the pressure and the irrotational body force. Error analysis is established to show the optimal rate of convergence. Numerical experiments are presented to validate the theoretical conclusions.

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Lin Mu. 2020-11-23. A Pressure-Robust Weak Galerkin Finite Element Method for Navier-Stokes Equations. https://arxiv.org/abs/2011.11526

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