A volume of fluid method for simulating fluid/fluid interfaces in contact with solid boundaries

TL;DR

This paper introduces a new volume of fluid method that explicitly models fluid/solid interaction forces, enabling accurate simulation of contact line dynamics and wetting phenomena in fluid interfaces with solid boundaries.

Contribution

The paper presents a novel approach to incorporate fluid/solid interaction forces into Navier-Stokes simulations using volume of fluid, allowing natural modeling of contact angles and wetting behavior.

Findings

Successfully simulates equilibrium drop shapes and spreading dynamics.

Captures contact line motion for various contact angles.

Provides a flexible framework for studying wetting phenomena.

Abstract

In this paper, we present a novel approach to model the fluid/solid interaction forces in a direct solver of the Navier-Stokes equations based on the volume of fluid interface tracking method. The key ingredient of the model is the explicit inclusion of the fluid/solid interaction forces into the governing equations. We show that the interaction forces lead to a partial wetting condition and in particular to a natural definition of the equilibrium contact angle. We present two numerical methods to discretize the interaction forces that enter the model; these two approaches differ in complexity and convergence. To validate the computational framework, we consider the application of these models to simulate two-dimensional drops at equilibrium, as well as drop spreading. We demonstrate that the model, by including the underlying physics, captures contact line dynamics for arbitrary contact angles. More generally, the approach permits novel means to study contact lines, as well as a diverse range of phenomena that previously could not be addressed in direct simulations.