Novel CFD-DEM approach for analyzing spherical and non-spherical shape particles in spouted fluidized bed

Abstract

The spouted fluidized bed process is a multiphase heat and mass transfer flow. The processrequires effective solid-gas and solid-solid interaction. Various numerical models have been devel-oped to understand and optimize these interactions. However, most of these models have usedspherical particle definition, whereas the actual particles are non-spherical. Here we presentcoupled Computational Fluid Dynamics(CFD) and Discrete Element Method(DEM) based model toanalyze the fluidized bed process for non-spherical particles (Faceted cylinder). The model resultsare validated with experimental results for spherical particles. The model is further used to under-stand mixing during the process as a function of non-spherical particle geometry. Aspect ratio andcorner count were the geometrical input parameters for faceted cylinder-shaped particles.Transient plots for bubble diameter and bed height for spouted fluidized beds were created forall cases. The bubble diameter and bed height values were much lower for faceted cylinder par-ticles than for spherical particles. For non-spherical particles, the increased number of corners wasa crucial factor that brought the outcomes closer to those of spherical-shaped particles. Theaspect ratio values increased, and the bubble diameter shrank as a result of more resistance toparticle movement. The results would be of great use to correctly simulate non- spherical particlesbased fluidized bed process and optimize various process parameters..

Rajat Mishra

Post-doctoral Scholar, IIT Bombay

Rajat completed his bachelor’s in Mechanical Engineering (2019) from SHUATS Allahabad. He joined Ph.D. program in Mechanical Engineering Department at IIT Gandhinagar in 2019. He is working on discrete element modelling in Additive Manufacturing. His interest also includes numerical modelling of heat transfer and fluid flow in Additive Manufacturing.