Model order reduction for bifurcating phenomena in Fluid-Structure Interaction problems

TL;DR

This paper develops an efficient reduced order model to analyze bifurcating phenomena like the Coand effect in fluid-structure interaction problems, highlighting the influence of elastic structures on bifurcation behavior.

Contribution

It introduces a branch-wise reduced order algorithm based on Proper Orthogonal Decomposition for fluid-structure interaction, extending previous models to better capture physics and bifurcation delays.

Findings

Nonlinear hyper-elastic laws delay bifurcation

Linear elastic solids further magnify bifurcation delay

Reduced order model improves computational efficiency

Abstract

This work explores the development and the analysis of an efficient reduced order model for the study of a bifurcating phenomenon, known as the Coand\u{a} effect, in a multi-physics setting involving fluid and solid media. Taking into consideration a Fluid-Structure Interaction problem, we aim at generalizing previous works towards a more reliable description of the physics involved. In particular, we provide several insights on how the introduction of an elastic structure influences the bifurcating behaviour. We have addressed the computational burden by developing a reduced order branch-wise algorithm based on a monolithic Proper Orthogonal Decomposition. We compared different constitutive relations for the solid, and we observed that a nonlinear hyper-elastic law delays the bifurcation w.r.t. the standard model, while the same effect is even magnified when considering linear elastic solid.