间隙泄漏流对轴流泵反向发电水力性能的影响  

Effect of Tip Leakage Flow on Hydraulic Performance of an Axial Flow Pump as Turbine

作　　者：阚阚 张清滢 郑源[1] 徐辉[2,3] KAN Kan;ZHANG Qingying;ZHENG Yuan;XU Hui(College of Energy and Electrical Engineering,Hohai University,Nanjing 211100,China;College of Water Conservancy and Hydropower Engineering,Hohai University,Nanjing 210098,China;College of Agricultural Science and Engineering,Hohai University,Nanjing 211100,China)

机构地区：[1]河海大学能源与电气学院,南京211100 [2]河海大学水利水电学院,南京210098 [3]河海大学农业科学与工程学院,南京211100

出　　处：《工程热物理学报》2023年第4期952-960,共9页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.52009033);江苏省自然科学基金资助项目(No.BK20200509);中央高校基本科研业务费专项资金资助项目(No.B210202066);中国博士后科学基金资助项目(No.2022M711021,No.2022T150185)。

摘　　要：本文以轴流泵反向发电为研究对象,采用数值方法研究了叶顶间隙泄漏流动(TLF)对轴流泵反向发电水力性能的影响机理。与无叶顶间隙的工况相比,TLF及其诱发的叶顶泄漏涡(TLV)会导致相同水头下水力效率下降和流量增加。TLF直接产生的TLV形式受叶轮叶片流入角度的影响,并且影响叶轮叶片表面的压力分布取决于运行条件。涡量输运方程分析表明,相对涡拉伸项在靠近叶轮壁面区域对TLV空间发展中起主导作用;在小流量和最优工况下,科氏力项在叶轮中部贡献最大;黏性扩散项作用最小。考虑间隙时,叶顶间隙内的泄漏流动及叶顶泄漏涡使得靠近壁面区域的涡量变化强度明显增强。研究成果为保障水泵反向发电安全稳定运行提供理论依据。Through numerical methods,this study investigates the mechanism of effect of TLF on hydraulic performance of an axial flow PAT.Compared with the condition without consideration tip clearance,TLF and the associated tip leakage vortex(TLV)are found to cause both the hydraulic efficiency drop and flow rate increase.The form of TLV directly generated by TLF is affected by the flow incidence angle,where in addition,the effect of TLF on pressure distribution mode around the blade depends of the machine fow conditions.The vorticity transport equation reveals that the relative vortex stretching term plays a dominant role in the TLV spatial development near the impeller shroud.The Coriolis force term has the largest contribution in the middle part of the impeller under low flow rate and optimal working conditions,while the viscous diffusion term has the least effect.When the clearance is considered,TLF results in significant increase of the vorticity variation intensity near the impeller shroud.The results provides theoretical basis for ensuring the safe and stable operation of PAT.

关 键 词：轴流泵 反向发电 叶顶泄漏涡 叶顶间隙 涡输运方程 

分 类 号：TH312[机械工程—机械制造及自动化]