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arXiv · 1506.02881

A combined finite volume - finite element scheme for a dispersive shallow water system

N. Aissiouene·M. -O. Bristeau·E. Godlewski·J. Sainte-Marie
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Abstract

We propose a variational framework for the resolution of a non-hydrostatic Saint-Venant type model with bottom topography. This model is a shallow water type approximation of the incompressible Euler system with free surface and slightly differs from the Green-Nagdhi model, see [13] for more details about the model derivation. The numerical approximation relies on a prediction-correction type scheme initially introduced by Chorin-Temam [17] to treat the incompressibility in the Navier-Stokes equations. The hyperbolic part of the system is approximated using a kinetic finite volume solver and the correction step implies to solve a mixed problem where the velocity and the pressure are defined in compatible finite element spaces. The resolution of the incompressibility constraint leads to an elliptic problem involving the non-hydrostatic part of the pressure. This step uses a variational formulation of a shallow water version of the incompressibility condition. Several numerical experiments are performed to confirm the relevance of our approach.

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N. Aissiouene, M. -O. Bristeau, E. Godlewski, J. Sainte-Marie. 2015-06-09. A combined finite volume - finite element scheme for a dispersive shallow water system. https://arxiv.org/abs/1506.02881

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