Interface-resolved simulation of droplet–particle interaction dynamics in multi-particle collisions

Understanding wet particle collisions involving droplets is essential for optimizing industrial processes. This study employs interface-resolved simulations combining the volume of fluid model, surface tension model, particle motion model, and overset grids to analyze particle–droplet interactions. Key phenomena investigated include particle motion, droplet spreading, successive particle collisions, and liquid bridge stretching. In symmetric systems, particle dynamics and droplet interactions show consistent patterns. The peak droplet spreading area increases with higher initial velocities and larger droplet sizes. Conversely, it decreases with greater liquid viscosity. Rotational velocity increases with higher collision velocity, lower viscosity, smaller droplet size, and is strongly influenced by collision angle, exhibiting trends similar to normal relative velocity. Increased initial collision velocity amplifies capillary and viscous forces, leading to greater energy dissipation. Force–displacement analysis confirms alignment between kinetic energy dissipation components and total energy loss. Moreover, larger droplets significantly enhance energy dissipation and reduce energy gain effects. Higher liquid viscosity further strengthens liquid bridge forces. These findings highlight the complex interactions involved in droplet-mediated particle collisions within multi-particle systems.