Numerical investigation on the effect of specularity coefficient on hydrodynamics of gas-solid flow in spout fluidized bed with draft plates

Numerical simulation of dense gas-solid flow in a spoutfluidized bed with draft plates was carried out using theEulerian-Eulerian multi-fluid approach incorporating thekinetic theory of granular flow (KTGF). To save thecomputational time, simulation was performed in twodimensionalframework. Different values of specularitycoefficient, which is important parameter of particle-wallboundary condition in, rang of 0.0001 to 0.1, were used.Numerical results show that by increasing the specularitycoefficient, time-averaged particle flux increases in spoutregion and decreases in annulus region. The best agreementof solid axial velocity with experimental data was achievedfor specularity coefficient equal to 0.03.