Comparison of CFD-DEM and TFM approaches for the simulation of the small scale challenge problem 1

Abstract The open source code MFIX is used to perform CFD-DEM and TFM simulations based on the small scale challenge problem 1 fluidized bed set up. The basic flow features such as the core-annulus structure and slugging dynamics are well predicted by both modeling approaches. Similarly the first four statistical moments of the particle velocity distributions from HsPIV measurements are equally reproduced qualitatively by the models. The predicted mean pressure drop is independent of the drag correlation used in both modeling frameworks but the CFD-DEM model gives predictions closer to the experimental values. Predicted fluctuating quantities such as rms and granular temperature show sensitivity to the drag model used. The TFM demonstrates greater accuracy over the CFD-DEM in prediction of the particle granular temperature while the opposite is true for the bubble granular temperature. CFD-DEM simulations on average take twice the time required to perform a TFM simulation.