不同比转数离心泵作透平研究

Research on Different Specific Speed Pumps Used as Turbines

摘要:

为了研究不同比转数离心泵用作透平时的差别，应用数值计算的方法对不同比转数的泵进行了研究，分析了泵作透平的效率与泵效率之间的关系，以及泵作透平时的流量、扬程换算系数随比转数变化的规律，并对不同比转数的泵内部功率损失分布进行了研究。研究结果表明：泵作透平的效率通常不高于泵的效率；泵在透平工况下的流量和扬程比泵工况的流量和扬程大，泵用作透平运行时的流量、扬程换算系数随比转数的增加而逐渐减小；功率损失分布分析表明，叶轮内部的功率损失是泵作透平内部主要的功率损失，并随比转数的增大而逐渐增大，因此对泵作透平的优化设计应当集中在对叶轮的研究。

Abstract:

With the aim to investigate the difference of different specific speed pumps used as turbines,numerical simulation of different specific speed pump was performed. The efficiency between its two modes and the variations of flow rate and pressure head conversion factors of pump as turbine (PAT) with different specific speed pumps were analyzed. Meanwhile, the power loss distribution within different specific speed PATs were presented. Results showed that the flow rate and pressure head were increased when a pump was operated as a turbine. The efficiency of PAT was no more than its pump mode. The flow rate and head conversion factors decreased with the increase of specific speed. Power loss distribution within each hydraulic part showed that it was the power loss within impeller that took up the majority of the total power loss and this tendency grew with the growth of specific speed. Therefore, the optimization design of PAT should focus on impeller research.