Topology-Preserving Coupling of Compressible Fluids and Thin Deformables

TL;DR

This paper introduces a new discretization method for coupled compressible fluids and thin deformable structures that guarantees leakproofness and accurate boundary resolution, enabling realistic simulations of complex fluid-structure interactions.

Contribution

The authors develop a Voronoi-based discretization combined with Godunov finite-volume integration that preserves domain connectivity and boundary sharpness for fluid-structure coupling.

Findings

Successfully simulates a balloon propelled by internal air

Models champagne cork ejection with friction effects

Simulates a supersonic asteroid impact

Abstract

We present a novel discretization of coupled compressible fluid and thin deformable structures that provides sufficient and necessary leakproofness by preserving the path connectedness of the fluid domain. Our method employs a constrained Voronoi-based spatial partitioning combined with Godunov-style finite-volume time integration. The fluid domain is discretized into cells that conform exactly to the fluid-solid interface, allowing boundary conditions to be sharply resolved exactly at the interface. This enables direct force exchange between the fluid and solid while ensuring that no fluid leaks through the solid, even when arbitrarily thin. We validate our approach on a series of challenging scenarios -- including a balloon propelled by internal compressed air, a champagne cork ejecting after overcoming friction, and a supersonic asteroid -- demonstrating bidirectional energy transfer between fluid and solid.