Meso-scale numerical analysis of the role of Van der Waals adhesion and static friction in fluidized beds of fine solids

ABSTRACT: This article explores the effect of Van der Waals force and static friction on the fluidization of fine solids using CFD-DEM simulations. The results show that both Van der Waals adhesion and static friction contribute to the pressure-drop hysteresis phenomenon. These results also demonstrate that to predict the homogeneous expansion of the bed across the range of velocities from the minimum required for fluidization to the minimum for bubbling, it is necessary to take into account the Van der Waals adhesion. The generated CFD-DEM dataset can guide the development of solid stress closures for two-fluid models to incorporate the effects of Van der Waals adhesion and static friction on fluidization hydrodynamics, allowing for the prediction of hysteresis in bed pressure drop at the macro-scale.