离心泵螺旋形压水室内流场的大涡模拟

Large Eddy Simulation of the Flow through the Spiral Casing of a Centrifugal Pump

用大涡模拟方法计算了离心泵螺旋形压水室内部非定常湍流。用具有二阶时间和空间精度的流线迎风有限元格式对滤波后的Navier-Stokes方程进行离散,用标准Smagorinsky模型作为亚格子尺度湍流模型。计算表明,按等速度矩法设计的压水室径向断面上存在较强的二次流,流动具有明显的非定常性。

Large eddy simulation of the internal turbulent flow through the spiral casing of a centrifugal pump is presented. A streamline-upwind finite element formulation with second-order accuracy both in time and space is used for discretizing the spatially-filtered Navier-Stokes equation represented in the Cartesian coordinates. The sub-grid scale model adopted in the present study is the standard Smagorinsky model combined with Van-Driest wall damping function. The result shows that there are obvious secondary cross flows on the cross-sections of the casing which is designed by the law of vur=const and the flow through it is an unsteady flow.