Axial Flow Pattern in a Concurrent Downflow Fluidized Bed (Downer) with Linearly Variable Superficial Gas Velocity
线性变气速下的下行床内轴向流动结构分析

A one-dimensional model is established to simulate the axial flow patterns in a downer reactor. Based on the gassolid continuity equation and the momentum equation, the model takes the variation of superficial gas velocity in the downer into account. The gas and solid velocity and the voidage distribution is emphatically studied.The simulation results show that there exists a remarkable disparity of axial flow pattern between variable superficial gas velocity and fixed gas velocity conditions. The linearly variable superficial velocity condition is more close to a downer reactor in practical operation.