双吸泵静腔室数值优化与试验分析

Numerical optimization and experimental analysis of the internal cavity in double-suction pump

【目标】探究影响双吸离心泵效率的主要因素及关键参数,优化设计吸水室以提高水力性能。【方法】基于水力损失最小原则,对吸水室与蜗壳内部流道形状进行设计,研究过流断面面积演变规律。采用CFD数值计算方法对优化前后的泵内流特征及性能特性进行对比分析,并利用实体模型试验验证优化方案的实际性能。【结果】改良设计的工况点效率比原型设计提升3.36%;在0.7QBEP(设计工况)至1.2QBEP范围内,整泵效率相较改进前模型均有所提高。其中,蜗壳水力损失降低明显,除1.3 QBEP损失下降6.18%以外,其余工况下蜗壳水力损失降低幅度均超过20%。对于吸水室,大于0.98 QBEP流量工况时,改进后模型吸水室损失低于改进前模型。【结论】吸水室、蜗壳内部流道的优化设计,明显改善了吸水室内部的不稳定流动,消除了叶轮出口附近的流动旋涡,显著降低水力损失,有效提升双吸泵的水力效率。

【Objective】The cavity chamber is a crucial component in double-suction pumps,and its design directly impacts pump performance.This study investigates the influence of key design parameters of the chamber on the efficiency of double-suction centrifugal pumps,aiming to optimize its design to enhance hydraulic performance of the pumps.【Method】Based on the principle of minimizing hydraulic loss,we designed the shapes of the chamber and the internal flow passages in the volute.We then examined the evolution of the cross-sectional area of the flow passages.Computational fluid dynamics(CFD)was used to compare the flow and performance characteristics of the pump before and after the optimization.The improved performance of the optimized design was evaluated against experimental results obtained from physical models.【Result】Compared to the original design without optimization,the optimized design increased efficiency of the pump at rated operating conditions by 3.36%.Within the range of 0.7 QBEP(design condition)to 1.2 QBEP,the optimized design improved overall pump efficiency compared to that without optimization.The optimization reduced the hydraulic losses across the volute significantly,with the reduction exceeding 20% under most operating conditions.At 1.3 QBEP,the reduction was 6.18%.For the chamber,the hydraulic losses in the optimized model were lower than those in the original model without optimization when flow rate exceeded 0.98 QBEP.【Conclusion】The optimized design of the suction chamber and the internal flow passages in the volute significantly improves flow stability in the suction chamber,eliminates vortices near the impeller outlet,reduces hydraulic losses,and enhances the hydraulic efficiency of the double-suction pumps.