The effects of collisional parameters on the hydrodynamics and heat transfer in spouted bed: A CFD-DEM study

An accurate prediction of particle collisions is of great importance to the success of modeling in fluidized beds, which depends on proper selection of collisional parameters. The present study aims to clarify the effects of collisional parameters on the hydrodynamics and heat transfer in a slot-rectangular spouted bed based on CFD-DEM simulations. We find that the macroscopic characteristics (i.e., the fountain height, solid velocity profiles and kinetic energy of solid phase) of the spouted bed are very sensitive to different collisional parameters, except the particle-wall restitution coefficient. It is observed that the increase of inter-particle restitution coefficient tends to suppress the translational movements of solid phase, and new insight is provided on the control mechanism of inter-particle restitution coefficient in the spouted bed. The results show that the raise in friction coefficient and rolling friction coefficient leads to decreased translational movements of solid phase. The effects of collisional parameters on the solid rotational movements are also analyzed. Moreover, the results demonstrate that heat transfer behaviors in the spouted bed are greatly affected by the area of dead zone, which is very sensitive to the friction and rolling friction coefficients. In comparison, the variation of collisional parameters mainly influences the conductive heat transfer and has minor impact on the convective heat transfer. (C) 2019 Elsevier B.V. All rights reserved.