A numerical study of cohesive and non-cohesive particles in a bottom spray fluidized bed using fully coupled CFD-DEM simulations

Fully coupled CFD-DEM simulations were conducted to investigate the applicability of the van der Waals cohesive force model to a bottom spray fluid bed. For the present simulation DEM was executed on the Graphic Unit Processing Unit (GPU) and the CFD on the Central Processing Unit (CPU). For this, DEM code XPS was coupled with CFD code AVL FIRERTM. Based on this approach a bottom spray fluid bed coater was simulated for a process of 30 sec to investigate the agglomeration process. The growth and breakage of agglomerates was numerically confirmed. Number of particles sprayed over the simulation time and mean velocity were monitored in both cohesive and non-cohesive systems to understand the behavior of fluidization. To understand the fluidization in the cohesive system three different cases of coating process were investigated with different fluidization velocities.