CFD Simulation and Experimental Investigation of the Hydrodynamic Behavior of a Gas–liquid–solid Fluidized Bed

Abstract

Gas–liquid–solid fluidized beds find numerous applications in industrial processes. Accurate prediction of the hydrodynamic behavior helps operate and design a gas–liquid–solid fluidized bed successfully. CFD is a powerful tool for predicting the gas–liquid–solid fluidized bed’s hydrodynamic behavior. In this current work, a three-phase fluidized bed's hydrodynamic behavior is simulated by applying the Eulerian-Eulerian granular multiphase model with a two-dimensional (2D) transient model and validated with the experimental outcomes. Hydrodynamic characteristics, bed expansion or bed voidage, bed pressure drop, and gas holdup are simulated and validated. It has been noticed that the expanded bed height increases with a rise in liquid velocity. At low liquid velocities, the bed height obtained from experiment and simulation differs; in experiment, a bed contraction is observed which is more prominent at higher gas velocities. Above all, the experiment and simulation's expanded bed height value agrees within 10% in beyond the minimum fluidization condition. The CFD simulation results reveal that the gas velocity causes a decline in bed pressure drop, validating the experimental findings. At lower liquid velocity values, the gas holdup values are very close, and at higher liquid velocity range, the agreement is within 20%. The strong concurrence among CFD simulation and experimental values for the current operating parameters demonstrates that the Eulerian-Eulerian multiphase granular flow method can predict a gas–liquid–solid fluidized bed's overall performance.