On the hydrodynamic behaviour of the immersed boundary -- lattice Boltzmann method for wetting problems

TL;DR

This paper investigates the hydrodynamic properties of a mesoscale immersed boundary-lattice Boltzmann model for wetting, comparing it with other solvers to understand its validity and limitations.

Contribution

It provides a detailed comparison of the IBLB model with BEM and VoF methods, highlighting its hydrodynamic behavior and contact-line modeling features.

Findings

The IBLB model effectively captures wetting dynamics with a wetting potential.

It prevents abrupt curvature changes near the contact line.

The model's hydrodynamic consistency is examined through comparisons.

Abstract

We study the hydrodynamic behaviour of a mesoscale numerical model for wetting dynamics based on the immersed boundary - lattice Boltzmann (IBLB) method. This IBLB model features a wetting potential to capture the interaction between a non-ideal droplet interface and a solid boundary; it is designed to prevent abrupt curvature changes near the contact line. As this approach prevents direct contact between the droplet and the solid, it forms a thin film beneath the droplet, which could compromise the hydrodynamic consistency in this region. This paper presents detailed comparisons against two other hydrodynamic solvers, respectively based on a boundary element method (BEM) and a volume of fluid (VoF) method, in order to examine the hydrodynamic behaviour of this IBLB scheme, elucidate its limits of validity in wetting applications, and explore the properties of its contact-line model.