撞击流气固两相流动中曳力模型的分析

为研究水平对称撞击流中气固两相曳力模型对球形颗粒运动的影响,运用FLUENT软件对spherical、stokes-Cunningham模型以及一种新型曳力模型下的气固两相流进行了数值模拟。新型曳力模型利用FLUENT中用户自定义函数(UDF)程序实现。采用欧拉-拉格朗日方法计算流场速度分布、进出口压力差、颗粒在撞击流装置停留时间以及颗粒运动轨迹。结果表明,采用新型曳力模型模拟撞击流气固两相流动,其速度分布基本关于撞击面对称分布。对于不同曳力模型,气固两相撞击流装置进出口的压力差在24. 9～25. 0 Pa之间。采用新型曳力模型模拟颗粒在撞击流装置停留时间主要分布在0. 4～1. 0 s,其颗粒运动现象与实验结果在定性上是一致的。

Analysis of Drag Force Model of gas-solid Phase Flow in Impinging Stream

In order to study the influence of gas-solid two-phase drag model on the motion of spherical particles in a horizontal symmetric impinging stream, the gas-solid two-phase flow under spherical, stokes-Cunningham and a new drag model was simulated by FLUENT software. The new drag force model is implemented using the User Defined Function (UDF) program in FLUENT. Euler-Lagrange method are used to calculate the velocity distribution, pressure difference at inlet and outlet, residence time of particles in impinging stream device and particle trajectory. The results show that the new drag force model is used to simulate the flow-solid two-phase flow, and its velocity distribution is basically symmetrically distributed on the impact surface. For different drag force models, pressure difference between inlet and outlet of gas-solid two-phase impinging stream device is between 24.9Pa and 25.0Pa. The residence time of particles in the impinging stream device is mainly 0.4-1.0s simulated by a new drag force model. The particle motion phenomena are qualitatively consistent with the experimental results.