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arXiv · 2409.17314

A Mixed finite element method for the velocity-pseudostress formulation of the Oseen eigenvalue problem

Felipe Lepe·Gonzalo Rivera·Jesus Vellojin
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Abstract

In this paper, we introduce and analyze a mixed formulation for the Oseen eigenvalue problem by introducing the pseudostress tensor as a new unknown, allowing us to eliminate the fluid pressure. The well-posedness of the solution operator is established using a fixed-point argument. For the numerical analysis, we use the tensorial versions of Raviart-Thomas and Brezzi-Douglas-Marini elements to approximate the pseudostress, and piecewise polynomials for the velocity. Convergence and a priori error estimates are derived based on compact operator theory. We present a series of numerical tests in two and three dimensions to confirm the theoretical findings.

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Felipe Lepe, Gonzalo Rivera, Jesus Vellojin. 2024-09-25. A Mixed finite element method for the velocity-pseudostress formulation of the Oseen eigenvalue problem. https://arxiv.org/abs/2409.17314

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