Heat Transfer and Pressure Drop Studies of Vertical Gas-Particle Flow Using a Variable Gas Property Two-Fluid Model

In the current work, the two-fluid model with variable gas properties is used to predict heat transfer and pressure drop in a vertical, adiabatic pipe. The simulation outcomes are compared between the variable and constant gas properties models. The simulation outcomes confirm that there is an insignificant deviation in the results of heat transfer, but there is a considerable deviation in the pressure drop data between the variable and constant gas properties models. The results also show that the restitution coefficients and specularity coefficient do not affect the simulation results. The effects of particle size, loading ratio, and inlet gas velocity on the thermo-hydrodynamic characteristics of gas-particle flows are studied. The simulation results show that there is enhanced heat transfer with increasing the gas-phase Reynolds number. Moreover, the gas-phase Prandtl number variation is not affected by the flow parameters. Finally, a correlation is proposed to predict the two-phase Nusselt number.