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arXiv · 2512.05642

Divergence-free decoupled finite element methods for incompressible flow problems

Volker John·Xu Li·Christian Merdon
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Abstract

Incompressible flows are modeled by a coupled system of partial differential equations for velocity and pressure, Starting from a divergence-free mixed method proposed in [John, Li, Merdon and Rui, Math. Models Methods Appl. Sci. 34(05):919--949, 2024], this paper proposes $\vecb{H}(\mathrm{div})$-conforming finite element methods which decouple the velocity and pressure by constructing divergence-free basis functions. Algorithmic issues like the computation of this basis and the imposition of non-homogeneous Dirichlet boundary conditions are discussed. Numerical studies at two- and three-dimensional Stokes problems compare the efficiency of the proposed methods with methods from the above mentioned paper.

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Volker John, Xu Li, Christian Merdon. 2025-12-05. Divergence-free decoupled finite element methods for incompressible flow problems. https://arxiv.org/abs/2512.05642

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