喷动床内气固二相流动行为的计算模拟

采用双流体模型结合颗粒动理学理论对喷动床内气固二相流体流动行为进行了计算模拟研究。模型中运用颗粒动理学理论描述颗粒相应力封闭流体控制方程,使用Gidaspow曳力模型描述气固相间作用。喷动床内颗粒在浓相区的体积分数很大,采用Schaeffer′s模型描述颗粒间的摩擦应力。模拟计算结果表明,喷动床内分喷射区、喷泉区、环隙区3个区域,在射流入口处形成一个瓶颈。模拟计算得到的颗粒速度和空隙度分布与实验数据进行比较,计算结果与实验结果吻合较好。

Calculational simulation of gas-solid flow behavior in spouted bed

The gas-solid flow behavior in spouted bed was simulated by using the two-fluid model and kinetic theory of granular flow. The kinetic theory of granular flow was applied to describe the granular stress to close the governing equations. The interaction between gas and solid was described by using the Gidaspow drag model. The particle volume fraction was high in the dense section of spouted bed. Schaeffer's model was applied to describe the frictional stresses between particles. The results show that there are three zones in spouted bed, i.e., the spout, the fountain and the annulus, and a bottleneck is formed near the jet inlet. The calculated particle velocity and voidage distribution in spouted bed are in good agreement with the experimental data.