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arXiv · 2103.11243

A mechanically consistent model for fluid-structure interactions with contact including seepage

Erik Burman·Miguel A. Fernández·Stefan Frei·Fannie M. Gerosa
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Abstract

We present a new approach for the mechanically consistent modelling and simulation of fluid-structure interactions with contact. The fundamental idea consists of combining a relaxed contact formulation with the modelling of seepage through a porous layer of co-dimension 1 during contact. For the latter, a Darcy model is considered in a thin porous layer attached to a solid boundary in the limit of infinitesimal thickness. In combination with a relaxation of the contact conditions the computational model is both mechanically consistent and simple to implement. We analyse the approach in detailed numerical studies with both thick- and thin-walled solids, within a fully Eulerian and an immersed approach for the fluid-structure interaction and using fitted and unfitted finite element discretisations.

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Erik Burman, Miguel A. Fernández, Stefan Frei, Fannie M. Gerosa. 2021-03-20. A mechanically consistent model for fluid-structure interactions with contact including seepage. https://doi.org/10.1016/j.cma.2022.114637

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