Equilibrium configurations of a 3D fluid-beam interaction problem

TL;DR

This paper investigates the equilibrium states of a 3D fluid-beam interaction, establishing existence and uniqueness of solutions in a static setting with complex fluid domain geometry.

Contribution

It provides the first rigorous proof of existence and uniqueness for a coupled 3D fluid-structure system with a non-smooth, non-simply connected domain in a static regime.

Findings

Existence of solutions under smallness conditions

Uniqueness of solutions in the static setting

Modeling of fluid-structure interaction with complex geometry

Abstract

We study a fluid-structure interaction problem between a viscous incompressible fluid and an elastic beam with fixed endpoints in a static setting. The 3D fluid domain is bounded, nonsmooth and non simply connected, the fluid is modeled by the stationary Navier-Stokes equations subject to inflow/outflow conditions. The structure is modeled by a stationary 1D beam equation with a load density involving the force exerted by the fluid and, thereby, may vary its position. In a smallness regime, we prove the existence and uniqueness of the solution to the PDE-ODE coupled system.