小流量工况双吸离心泵能量损失及受力特性分析

Energy Loss and Force Analysis of Double Suction Centrifugal Pump Under Low Flow Rate Condition

为了深入分析小流量工况下双吸式离心泵的能量特性和运行稳定性,本文采用数值模拟的方法研究了不同流量下泵内的熵产损失分布和叶轮受力特性,并通过试验验证证明了计算结果的准确性。研究结果表明:叶轮和蜗壳内的损失是泵损失的主要来源,叶轮损失占比在20%~43%之间,蜗壳的损失占比在54%~73%之间;叶轮内由于动静干涉引起的脉动损失占比更高,蜗壳内壁面损失占比更高。隔板在小流量下的适用性差,其存在不仅会诱发动静干扰带来额外的流动损失,而且会压缩相应流道增加不必要的壁面损失;叶轮所受径向力随流量增大呈先减小后增大的趋势,额定工况点附近受力最小。

In order to analyze the energy characteristics and operation stability of double-suction centrifugal pump at low flow rate,the distribution of entropy generation loss and the force characteristics of impeller were studied by numerical simulation.The accuracy of the simulation results is verified by experiments.The results show that the losses in impeller and volute are the main sources of pump losses,and the ratio of pulsation losses in impeller and volute is higher than that in volute.The separators are not suitable for small flow rate.The existence of the separators will not only cause additional flow loss due to static and dynamic interference,but also compress the corresponding flow channels and increase unnecessary wall loss The radial force flow of impeller decreases first and then increases,and the force near the rated working point is the least.