Comparison of continuum models using the kinetic theory of granular flow with discrete particle models and experiments: extent of particle mixing induced by bubbles

The bubble formation and extent of particle mixing induced by a single bubble injected in a mono-disperse fluidised bed at incipient fluidisation conditions has been studied with a Two-Fluid continuum Model (TFM) using the Kinetic Theory of Granular Flow (KTGF) and com- pared with experiments and simulation results obtained from a Discrete Particle Model (DPM). The effect of different gas-particle drag models and frictional viscosity models on the bubble behaviour and extent of particle mixing has been assessed. To describe the extent of particle mixing well, a frictional viscosity model needs to be included, however, the currently available frictional viscosity models need further improvement