流动参对导叶式旋风管内固相颗粒运动影响的数值模拟

摘要

对导叶式旋风管内气、固两相进行数值模拟,从颗粒在排尘锥内不同位置的碰撞概率、返混情况、停留时间分布3个方面对颗粒的运动情况进行描述,研究不同流动参数下颗粒的运动变化结果表明,在排尘锥两侧缝环面的重叠处,颗粒的碰撞概率达到最大值,此处结垢和磨损的可能性较大；随着颗粒粒径的增大,直接捕集的比例增大,排尘锥返混和灰斗返混的比例减小,并且排尘锥返混多于灰斗返混;在一定的流量范围内,随着流量的减小,颗粒返混现象加重,并且随着粒径的减小,相同粒径的颗粒在分离空间内和排尘锥内停留时间延长的幅度变大,返混现象更加明显.%The gas flow and solid field in cyclone tube was simulated.The movements of particles were described from 3 aspects which were the collision probability in different positions of dust discharge cone,back-mixing phenomenon and residence time distribution of particles.The results show that in the torus intersection with side seam,the collision probability reaches the highest,and the probability of wear or scaling is the biggest.As the particle diameter increases,the direct trapping proportion increases,and the back mixing proportion from the discharge dust port and ash bucket decreases.The proportion of back mixing from the discharge dust port is more than that from ash bucket.Within a certain flow rate range,the phenomenon of back mixing becomes serious with the less flow rate.With the particles diameter decreasing,the growth rate of particles residence time distribution in separation space and dust discharge cone becomes bigger,and the phenomenon of back mixing becomes serious.