A revised drag force model and the application for the gas–solid flow in the high-density circulating fluidized bed

The behavior of the gas–solid two-phase flow plays a vital role in the heat and mass transfer in the high-density circulating fluidized bed. In this paper, based on the energy-minimization multi-scale (EMMS) model, a drag force coefficient model, which can be applied to different kinds of particle, is developed for investigating the hydrodynamic characteristics of the high-density circulating fluidized bed (HDCFB). Coupled with the two-fluid model and the kinetic theory of granular, a 3D full-loop numerical simulation is implemented to test the validity of the revised drag force coefficient model, and excellent numerical performances and encouraging results are obtained. Under the operated conditions, the simulation results are in excellent agreement with the experimental data, which reveals that the revised drag force coefficient model is competent for the HDCFB’s numerical simulation.