基于摩擦-动力应力模型模拟喷动床气固流动

NUMERICAL SIMULATION OF GAS-SOLID FLOWS IN SPOUTED BEDS WITH FRICTIONAL-KINETIC STRESSES MODEL

建立同时考虑颗粒和颗粒之间瞬间碰撞作用(瞬间接触)和非流化下颗粒滑动和滚动运动产生的颗粒半接触作用的颗粒碰撞-摩擦应力模型。推导具有普适性的固相动量守恒方程,建立高颗粒浓度气固两相流动模型,对喷动床内气体颗粒流动过程进行了数值模拟。模拟计算预测喷动床内喷射区、环隙区和喷泉区颗粒流动特性。预测喷动床内颗粒浓度和速度分布与他人实验结果相吻合。

Considering both instantaneous collision and contacting by rolling between particles,a frictional-kinetic stresses model of particles is proposed.The collisional interaction of particles is predicted by kinetic theory of granular flow,while the sustained contact force is calculated from a friction stress model.An inverse tangent function is used to provide a smooth transitioning from the plastic and viscous regimes.Flow behavior of particles is simulated in a spouted bed.The distributions of concentration,velocity and granular temperature of particles are obtained.Calculated particle velocities and concentrations in the spouted beds are in agreement with experimental data published in literature.