Solid-Fluid Interaction with Surface-Tension-Dominant Contact

TL;DR

This paper introduces a new three-way coupling method for simulating solid-fluid interactions dominated by surface tension, accurately modeling phenomena like floating objects and surface effects.

Contribution

It presents a novel physical model with a thin liquid membrane and a hybrid numerical framework, enabling realistic simulation of surface-tension-driven contact phenomena.

Findings

Objects with higher density than water can float due to surface tension.

Floating objects attract each other, demonstrating the Cheerios effect.

Surface tension weakening effects are observed with surface-active agents.

Abstract

We propose a novel three-way coupling method to model the contact interaction between solid and fluid driven by strong surface tension. At the heart of our physical model is a thin liquid membrane that simultaneously couples to both the liquid volume and the rigid objects, facilitating accurate momentum transfer, collision processing, and surface tension calculation. This model is implemented numerically under a hybrid Eulerian-Lagrangian framework where the membrane is modelled as a simplicial mesh and the liquid volume is simulated on a background Cartesian grid. We devise a monolithic solver to solve the interactions among the three systems of liquid, solid, and membrane. We demonstrate the efficacy of our method through an array of rigid-fluid contact simulations dominated by strong surface tension, which enables the faithful modeling of a host of new surface-tension-dominant phenomena including: objects with higher density than water can keep afloat on top of it; 'Cheerios effect' about floating objects that do not normally float attract one another; surface tension weakening effect caused by surface-active constituents.