Wetting boundary conditions for multicomponent pseudopotential lattice Boltzmann

TL;DR

This paper addresses the challenge of implementing accurate wetting boundary conditions in multicomponent lattice Boltzmann simulations, especially on curved surfaces, by extending a previous strategy for multiphase models.

Contribution

It introduces an extended boundary condition strategy that improves accuracy for liquid-wall interactions in complex geometries within multicomponent lattice Boltzmann models.

Findings

Existing methods are accurate only on aligned walls.

The proposed strategy improves accuracy on curved surfaces.

Application demonstrated with droplet coalescence on curved surfaces.

Abstract

The implementation of boundary conditions is among the most challenging parts of modeling fluid flow through channels and complex media. Here, we show that the existing methods to deal with liquid-wall interactions using multicomponent Lattice Boltzmann are accurate when the wall is aligned with the main axes of the lattice but fail otherwise. To solve this problem, we extend a strategy previously developed for multiphase models. As an example, we study the coalescence of two droplets on a curved surface in two dimensions. The strategy proposed here is of special relevance for binary flows in complex geometries.