时间推进法求解离心泵内部不可压流场

NUMERICAL SIMULATION FOR THE INCOMPRESSIBLE FLOW FIELDS IN A CENTRIFUGAL PUMP BY USING OF TIME MARCHING METHOD

本文使用时间推进法求解离心泵内部不可压缩流的紊流时均Reynolds方程。选用Boldwin-Lomax双层代数紊流模型,对流项采用中心差分格式离散,时间推进项选用四阶显式Runge-Kutta求解方法。对离心泵在0.4、1.0、1.5倍的设计工况点进行了数值计算。计算所得到的流量扬程点与实验值相吻合,在小流量工况点效率吻合很好,在设计工况和大流量工况点效率偏高,文中讨论了叶轮出口压力分布、蜗壳外壁面上的静压分布及载荷随叶轮半径的变化规律。

In this paper the incompressible Reynolds-aver aged Navier-Stokes equations for the centrifugal pump were solved by using of time marching method. The Boldwin-Lomax two layer turbulent model was selected. The type of spatial discretization was central scheme. An explicit four-stage Rung-Kutta was implemented to solve the time marching terms. Three operation points, at the flow rates of 0.4, 1.0, 1.5 ones at the best efficiency point, were selected to simulate respectively. The calculated values of flow rate and head were coincided with the experiments data well, at the small flow rate the value of efficiency is equal to the measurements data almost, while at the best efficiency point and the large flow rate the calculated efficiency is higher than the experiments one. The pressure distribution at the outlet of the impeller and the static pressure at the outer wall of the volute and the relationship between the flow fields in the blade-to-blade and the blade load were discussed in the paper.