Lattice Boltzmann study of the interaction between a single solid particle and a thin liquid film

Abstract

The isothermal single-component multi-phase lattice Boltzmann method (LBM) combined with the particle motion model is used to simulate the detailed process of liquid film rupture induced by a single spherical particle. The entire process of the liquid film rupture can be divided into two stages. In Stage 1, the particle contacts with the liquid film and moves into it due to the interfacial force and finally penetrates the liquid film. Then in Stage 2, the upper and lower liquid surfaces of the thin film are driven by the capillary force and approach to each other along the surface of the particle, resulting in a complete rupture. It is found that a hydrophobic particle with a contact angle of 106.7° shows the shortest rupture duration when the liquid film thickness is less than the particle radius. When the thickness of the liquid film is greater than the immersed depth of the particle at equilibrium, the time of liquid film rupture caused by a hydrophobic particle will be increased. On the other hand, a moderately hydrophilic particle can form a bridge in the middle of the liquid film to enhance the stability of the thin liquid film.