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

TL;DR

This paper introduces a new mechanically consistent fluid-structure interaction model that incorporates contact and seepage effects using a relaxed contact formulation and Darcy-based seepage modeling, applicable to various geometries and discretizations.

Contribution

It presents a novel combined approach for contact and seepage in fluid-structure interactions, ensuring mechanical consistency and ease of implementation.

Findings

The model accurately captures seepage during contact.

Numerical studies validate the approach for different solid geometries.

The method is compatible with various discretization techniques.

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.