A Model Based on Two-Fluid Theory for Predicting Hydrodynamic Behavior in 3D Fluidized Bed: I. Homogeneous and Bubbling Fluidization of Gas-Solid Systems

摘要: A mathematical model,including additional terms in both the gas-and solid-phase momentum equations based on two-fluid theory by considering particle-fluid interactions under a quasi-equilibrium state,was employed to explore homogenous fluidization of Geldart particle and bubbling/collapsing B 3D gas-fluidized beds.The main features this model are that characteristic length is order diameter only correlation for drag force coefficient necessary close governing equations.Transient calculations within bed 0.2 m(long) × m(wide) 0.5 m(high) were conducted platform commercial software package,CFX 4.4,by adding user-defined Fortran subroutines.To verify numerical procedure,two kinds particles simulated at superficial gas velocity umf 1.5umf,and results showed homogenously expanding behavior nature.Then effect disturbances local voidage solid profile grid scale,and overall pressure drop equipment scale investigated numerically two particles.Bubbling collapsing during bubbling process averaged height standard deviation interface collapse probed one kind particles.The above simulations fair agreement with classic Geldart,experiment simulation literature,indicating can be used predict homogeneous fluidized beds.