VOF‐DEM numerical study of mesoscale bubble dynamics in the gas‐liquid‐solid three‐phase flow system

Mesoscale bubble dynamics play a critical role in governing the overall performance of gas‐liquid‐solid systems. In this study, the volume of fluid method coupled with a discrete element method is utilized to scrutinize the mesoscale bubble dynamics within a gas‐liquid‐solid system featuring a dense particle bed. The results reveal that the squeezing effect of the particle bed induces a bubble pairs regime, which causes the bubble collision, coalescence and breakup, thereby generating daughter bubbles. Additionally, the combined influence of large size, flattened shape, off‐center collisions and the exists of particles facilitate bubble wakes to transform from closed into asymmetrical open patterns, further causing particles released from bubble wakes. Finally, the high‐speed region is predominantly confined to the bubble wake area, resulting in a diminished overall stirring capability compared with two‐phase system. The insights obtained from this study shed valuable light on bubble behaviors within gas‐liquid‐solid systems, offering implications for further study in this field.