Decoupling methods for fluid-structure interaction with local time-stepping

TL;DR

This paper introduces two innovative global-in-time domain decomposition methods for fluid-structure interaction problems, enabling independent subdomain solutions with different time discretizations, thereby improving simulation efficiency.

Contribution

The paper presents novel Steklov-Poincare and Robin methods that formulate coupled systems as space-time interface problems, allowing flexible time-stepping in subdomains.

Findings

Methods demonstrate high accuracy in numerical tests.

Significant efficiency gains with different time step sizes.

Applicable to both physical and non-physical problems.

Abstract

We introduce two global-in-time domain decomposition methods, namely the Steklov-Poincare method and the Robin method, for solving a fluid-structure interaction system. These methods allow us to formulate the coupled system as a space-time interface problem and apply iterative algorithms directly to the evolutionary problem. Each time-dependent subdomain problem is solved independently, which enables the use of different time discretization schemes and time step sizes in the subsystems. This leads to an efficient way of simulating time-dependent phenomena. We present numerical tests for both non-physical and physical problems, with various mesh sizes and time step sizes to demonstrate the accuracy and efficiency of the proposed methods.