CFD-VOF-DPM simulations of bubble rising and coalescence in low hold-up particle-liquid suspension systems

A combined CFD–VOF–DPM method has been used to simulate bubble rising and coalescence phenomenon in low hold-upparticle–liquid suspension systems. The liquid is considered as the primary phase, while particles are considered as the discrete phase. Bubbles or bubble parcels are regarded as the gas phase modeled using the VOF method. On the basis of the independence analysis of grid and time-step sizes, the combined method predicts fluid dynamics accurately with slight discrepancy according to the validation with experimental results. Subsequently, three-phase hydrodynamics are systematically investigated and thoroughly discussed.