Chemical Engineering Science, Vol.65, No.9, 2664-2679, 2010
Flow of gas and particles in a bubbling fluidized bed with a filtered two-fluid model
Numerical simulations of gas-particles flow in a bubble fluidized bed with two large eddy simulations of gas and solid phases are presented. For gas phase and solid phase, the sub-grid scale model for the viscosity is based on the Smagorinsky form. The sub-grid model for the particle pressure proposed by Igci et al. (2008) is modified by replacing the minimum fluidization velocity. The collisional interaction of particles is considered by the kinetic theory of granular flow. Flow behavior of gas and particles is performed by means of these two sub-grid scale models. The subgrid closure for the particle phase viscosity and pressure led to a qualitative change in the simulation results. Predictions are compared with experimental data measured by Yuu et al. (2000) and Taghipour et al. (2005) in the bubbling fluidized beds. The distributions of concentration and velocity of particles are predicted in the bubbling fluidized bed. The predicted filtered particle phase pressure increases and the filtered particle phase viscosity decreases with the increase of particle concentration. The qualitative importance of the model constant c(s) of particles is demonstrated. (C) 2010 Elsevier Ltd. All rights reserved.
Keywords:Large eddy simulation;Subgrid-scale model;Kinetic theory of granular flow;Two-fluid model;Numerical simulation;Bubbling fluidized bed