Modeling of collection of non-spherical particle assemblies by liquid droplets under potential flow conditions

Abstract

A model, which explains the collection of non-spherical particle assemblies by liquid droplets, was constructed. The system was investigated under potential flow conditions. It was possible to generate the streamlines around the particles and droplets via potential flow theory. Therefore, the complexity coming from eddies and vorticity was eliminated. Non-spherical particles and agglomerated particles were modeled using equivalent diameter assumption due to the boundary layer, rotation, and oscillation behaviors of the particles. Collection probability was calculated as a function of three different collection mechanisms: collision, adhesion, and engulfment. The interaction forces between particles and droplets were divided into two groups as external and internal forces. The gravitational force and the drag force due to the uniform flow rate caused collection mechanisms. Van der Waals and Electrostatic interactions were investigated in order to explain adhesion and wetting mechanisms. Through simulations, we have found that particle and droplet diameters were the most influencing parameters on the collision mechanism. The engulfment possibility could be increased by adding surfactant to the liquid solution. The results of this model showed similarities with the other models in the literature, as well as with that of the experimental studies.