Development of a numerical model for the hydrodynamics simulation of liquid-solid circulating fluidized beds

Due to extensive applications of the liquid-solid circulating fluidized beds (LSCFBs) in biochemical and petroleum industries, a detailed computational fluid dynamics (CFD) study is crucial to understand the flow characteristics in LSCFBs. In this paper, the hydrodynamics in LSCFBs is numerically investigated using the Eulerian-Eulerian two-phase model combined with the kinetic theory for the granular phase (KTGP). Key factors affecting the simulation results including the drag model, near wall treatment and boundary conditions are investigated, and the CFD model is validated by comparing the numerical results with the experimental data. Among the seven different drag models examined in this study, the adjusted Syamlal O'Brien drag model and the irregular particle drag model are found to provide the best numerical solutions for spherical and irregular particles, respectively. As for the three different near wall treatments tested, the Menter-Lechner near wall treatment is found to provide the best numerical predictions in the near wall region.