Computational fluid dynamic simulation based cluster structures-dependent drag coefficient model in dual circulating fluidized beds of chemical looping combustion

A computational fluid dynamic (CFD) model for the dual circulating fluidized beds of chemical looping combustion technology has been developed. A continuum two-fluid model is used to describe both the gas and solid phases. Detailed submodels to account for fluid-particle and particle-particle interaction forces were incorporated. The gas-solids drag coefficient is predicted by means of the cluster structures-dependent (CSD) drag coefficient model. Flow behavior of gas and particles in the air reactor (AR) and fuel reactor (FR) is predicted. The solid circulation rate increases with the increase of solids inventory of the AR and FR. When the loop seal is connected to dual circulating fluidized beds of AR and FR, the fluidizing state of AR and FR is found to be affected by hydrodynamics in the loop seals.