Lattice Boltzmann simulation of capillary interactions among colloidal particles

Abstract

We present a numerical model for dynamic simulation of colloidal particles attached to a fluid interface. A new coupling method is proposed for combining Newtonian dynamics for colloidal particles and the lattice Boltzmann method for fluid phases so as to account for the wetting properties of particle surfaces. With this feature, capillary interaction of colloidal particles, in addition to electrostatic and hydrodynamic interactions, can be simulated.For the validation of the proposed model, we perform numerical simulations of the steady flow around a square array of cylinders, the transient dynamics of a moving particle in the quiescent solvent, as well as the contact angle of a colloidal particle attached to the multi-component fluid interface. Further, we apply the current model to simulate capillary interactions between two colloidal particles at a fluid interface. Effects of the relevant physical parameters on the dynamics of the particles, in particular, wettability and gravity, are investigated.

Lattice Boltzmann method for simulation of wettable particles at a fluid-fluid interface under gravity

“…(59). Similar systems were investigated by Onishi et al [19], where the contact angle of the particle was restricted to α = 90 • in Eqs. (54)-(59) and the second term of Eq.…”

“…Similar systems were investigated in previous studies [19][20][21]35], where the motions of particles were evaluated qualitatively. Onishi et al [19] compared simulation results with theoretical results, where the mass density and contact angle of the particles were restricted to ρ p > ρ f and α = 90 • , respectively. In this study, the capillary flotation force between two particles with arbitrary values of ρ p and α was theoretically formulated, and comparisons between the simulation and theoretical results are presented.…”

“…It is essential to select appropriate solid-fluid and fluid-fluid simulation methods for a target system and couple such methods efficiently. Therefore, various types of coupling methods have been developed, and new methods continue to be studied [19][20][21][22].…”

Dynamic wetting: status and prospective of single particle based experiments and simulations

“…Furthermore, these methods have been used to study particle covered droplets or particles at interfaces under the influence of external fields [13,47,88]. Static wetting effects can be easily controlled by tuning, for example, the surface properties of the particles and parameters such as the particle contact angle are directly accessible from the fluid concentration fields obtained in the simulation [86,[89][90][91].…”

Lattice Boltzmann Simulation of Particle Motion in Binary Immiscible Fluids

“…Particle suspension in multiphase or multicomponent flows has gained increasing attention during the last decade [3,4,16,20,23,24,28,32,41,42], due to the extensive use of particles to stablize emulsions, which has many applications in food, cosmetics and medical industires [23], as well as the use of proppants in hydraulic fracturing for unconventional gas production [36]. Also, in many processes, such as hydrocarbon recovery, geologic CO 2 sequestration, and soil wetting and drying, understanding the emergent patterns of the invasion of one fluid into a deformable porous medium filled with another fluid is both scientifically fascinating and technologically important [21].…”