基于CFD的球阀阀腔流场的数值仿真

Numerical Simulation of Flow Field of the Ball Valve Cavity Based on CFD

用SST湍流模型封闭的雷诺平均N-S方程组,对球阀在不同开度下的三维流场进行了数值仿真,同时针对球阀结构,建立了不同阀腔通径的流场模型,计算了其不均匀度和流量系数,分析了阀腔对流场的影响。结果表明,在一定开度下,球阀阀芯通道内会形成一对大小相等、方向相反的涡流,在阀后出口管道内会形成两对方向相反的涡流,其中靠近节流口的涡流尺度较小;阀腔会增加流场内部的扰动,并且随阀腔空间的增大,扰动也在增加。研究结果为球阀阀腔结构的优化设计提供了参考。

The 3-D flow field of the ball valve at different degrees of opening is numerical simulated with Reynolds average N-S equations closed by SST Turbulence Model.And regarding the valve＇ s structure,the valve cavities with different diameters are built and simulated.The influence on the whole flow field by valve cavity is analysed from the computed nonuniformity level and discharge coefficient.The results show that,at a certain degree of opening,a pair of vortexes with the same size but contrary directions will form in the spool passage,and two pairs of vortexes will emerge in the export pipe after the valve,and among them,the vortexes closed to the orifice are smaller.The valve cavity will increase the disturbance in the flow field,and with the aggrandizement of valve chamber space,more and more disturbance will arise.The results can provide a reference on the optimal design of the structure of ball valve cavity.