Chemical Engineering & Technology, Vol.34, No.12, 2059-2068, 2011
Modeling of Gas-Particle Turbulent Flow in Spout-Fluid Bed by Computational Fluid Dynamics with Discrete Element Method
Gas and solid turbulent flow in a cylindrical spout-fluid bed with conical base were investigated by incorporating various gas-particle interaction models for two-way coupling simulation of discrete particle dynamics. The gas flow field was computed by a k-? two-equation turbulent model, the motion of solid particles was modeled by the discrete element method. Drag force, contact force, Saffman lift force, Magnus lift force and gravitational force acting on individual particles were considered in the mathematical models. Calculations on the cylindrical spout-fluid bed with an inside diameter of 152?mm, a height of 700?mm, a conical base of 60 degrees and the ratio of void area of 3.2?% were carried out. Based on the simulation, the gas-solid flow patterns at various spouting gas velocities are presented. Besides, the changes in particle velocity, particle concentration, collision energy, particle and gas turbulent intensities at different proportions of fluidizing gas to total gas flow are discussed.