网格划分对多级离心泵水力性能计算精度的影响

Research on the Influence of Grid Division on the Hydraulic Performance Calculation Accuracy of Multistage Centrifugal Pump

为提高多级离心泵在多工况条件下水力性能的计算精度,分别将计算域划分为四面体、混合型和六面体网格,采用RNGκ-ε湍流模型进行数值计算,与试验结果作对比,从计算曲线与试验曲线的吻合度上综合评判网格划分对计算精度的影响。研究结果表明:混合型和六面体网格在多工况条件下的综合计算精度高于四面体网格,而六面体网格的综合计算精度又明显优于混合型网格;六面体网格对各性能参数的最大相对计算误差不超过2.44%,效率的计算曲线和试验曲线吻合度较高。综合来看,六面体网格更适合于多级离心泵的水力性能预测。

In order to improve the calculation accuracy of the hydraulic performance of multistage centrifugal pump under multiple working conditions,the calculation domain was divided into tetrahedral,mixed and hexahedral grids respectively.RNGκ-εturbulence model was used for numerical calculation and compared with the test results.The influence of grid division on the calculation accuracy was comprehensively evaluated from the coincidence of the calculation curve and the test curve.The results show that the comprehensive calculation accuracy of hybrid and hexahedral grid schemes is higher than that of tetrahedral grid under multi-working conditions;the comprehensive calculation accuracy of hexahedral grid is significantly better than that of hybrid grid type,especially that the maximum relative calculation error of performance parameters under multi working conditions is less than 2.44%,and the efficiency calculation curve and test curve are in good agreement.In general,hexahedral grid is suitable for the prediction of the hydraulic performance of multistage centrifugal pump.