旋风分离器内旋转流偏心旋转对速度计算的影响

摘要

The strong swirl gas-phase flow field in a cyclone was numerically simulated by Fluent .The results indicate that there exists a deviation of the center of the swirling flow and the geometric center of the cyclone , so the swirling flow is an eccentric rotation .The velocities in swirling flow field by CFD were calculated based on the geometrical center , which is different from that on the center of swirling flow .Therefore, the tangential velocity and radial velocity based on the geometrical center must be modified to the velocities based on the center of swirling flow before the flow field is applied to the prediction of the cyclone performance .Furthermore , the method was deduced and given for velocity transform between the different centers according to the simulated flow field .%采用Fluent软件对旋风分离器内流场进行了数值模拟，结果表明其旋转流存在着偏心旋转现象，即旋转流的旋转中心与旋风分离器的几何中心不重合。用CFD计算旋风分离器内强旋流的三维速度是基于旋风分离器的几何中心给定的，而进行气固分离计算用的三维速度是基于旋转中心的，二者之间存在着一定的差别，尤其是径向速度分布上有很大的不同。这就需要对基于几何中心的旋风分离器内旋转流的三维速度值进行修正，将参考几何中心计算的流场变换为参考旋转中心的流场。在旋风分离器流场数值模拟的基础上，分析了基准不同所产生的三维速度分量之间变化，给出了将参考几何中心计算的流场换算到参考旋转中心的流场的方法。