Numerical simulations of complex fluid-fluid interface dynamics

TL;DR

This paper reviews numerical simulation techniques for complex fluid-fluid interface dynamics, focusing on three coupled methods with lattice Boltzmann for studying deformable interfaces in industrially relevant systems.

Contribution

It critically compares three numerical schemes integrated with lattice Boltzmann to model complex fluid interfaces, including vesicles, surfactants, and nanoparticles.

Findings

Evaluates the strengths and limitations of each numerical scheme.

Provides insights into interface deformation and stabilization mechanisms.

Facilitates better understanding of industrial emulsion processes.

Abstract

Interfaces between two fluids are ubiquitous and of special importance for industrial applications, e.g., stabilisation of emulsions. The dynamics of fluid-fluid interfaces is difficult to study because these interfaces are usually deformable and their shapes are not known a priori. Since experiments do not provide access to all observables of interest, computer simulations pose attractive alternatives to gain insight into the physics of interfaces. In the present article, we restrict ourselves to systems with dimensions comparable to the lateral interface extensions. We provide a critical discussion of three numerical schemes coupled to the lattice Boltzmann method as a solver for the hydrodynamics of the problem: (a) the immersed boundary method for the simulation of vesicles and capsules, the Shan-Chen pseudopotential approach for multi-component fluids in combination with (b) an additional advection-diffusion component for surfactant modelling and (c) a molecular dynamics algorithm for the simulation of nanoparticles acting as emulsifiers.