CFD-DEM simulation of heat transfer in spout-fluid beds

Abstract

It is necessary to study the flow regimes of spout-fluid beds before considering their application in the industry. A three-dimensional computational fluid dynamic coupled with the discrete element method (CFD-DEM) was employed to study the heat transfer of the jet-in-fluidized bed flow, spouting-with-aeration flow, and intermediate/spout-fluidization flow regimes of the spout-fluid bed. To determine the efficiency of heat transfer in these flow regimes, extensive CFD-DEM simulations were conducted along with a heat transfer model. The heat transfer in these flow regimes was investigated using particle temperature distributions, mean convective heat flux, and average particle temperature. Compared to the other flow regimes, the jet-in-fluidized bed flow regime demonstrated a higher degree of heat transfer due to the presence of bubbles in the annulus. Moreover, it was observed that the spouting-with-aeration flow regime exhibits a better convective heat transfer compared to the intermediate/spout-fluidization. The stable and continuous spout channel of the spouting-with-aeration flow regime helps convective heat transfer more than the interrupting spout channel of the intermediate/spout-fluidization.