叶顶泄漏流动对轴流泵反向发电能量特性的影响研究  

Tip Leakage Flow on Energy Performance for an Axial Flow Pump as Turbine

作　　者：阚阚 张清滢 黄佳程 龚严 KAN Kan;ZHANG Qingying;HUANG Jiacheng;GONG Yan(College of Energy and Electrical Engineering,Hohai University,Nanjing 211100,China;College of Agricultural Science and Engineering,Hohai University,Nanjingg 210098,China)

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

出　　处：《工程热物理学报》2023年第9期2416-2422,共7页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.520609033);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(No.B210202066);中国博士后科学基金(No.2022M711021)。

摘　　要：轴流泵端壁区存在叶顶间隙从而引起叶顶泄漏流动,严重限制了轴流泵反向发电(PAT)的能量性能和稳定性。为了研究叶顶泄漏流动(TLF)对轴流泵反向发电能量特性的影响,对轴流泵反向发电不同流量工况进行了数值模拟。计算结果表明:相比于不考虑间隙的情况,考虑叶顶间隙时模拟的水头和效率较低,且两种间隙下的差异随着流量的增加而增大,TLF和其引起的叶顶间隙涡(TLV)是造成此差异的主要原因。入流角对TLV空间形式有影响,而TLV对叶轮叶片表面压力分布的影响取决于运行条件。涡输运方程表明,涡拉伸项在TLV的空间演化中起主导作用,黏性扩散项作用最小。Tip clearance existing in the region between the impeller blade tip and shroud of the axial flow pump leads to tip leakage flow,which seriously limits the energy performance and stability of an axial flow pump as turbine(PAT).In order to investigate the influence of tip leakage fow(TLF)on the energy characteristics of the axial flow PAT,numerical simulations are carried out under different flow conditions.The results show that,compared with the case without considering the clearance,the simulated head and efficiency are lower when considering the tip clearance,and the difference between zero clearance and with clearance increases with the increase of the fow rate.TLF and the tip leakage vortex(TLV)caused by TLF are the main reasons for the difference.The inflow angle has an effect on the spatial distribution of TLV,and the influence of TLV on the pressure distribution on the impeller blade surface depends on the operating conditions.The vorticity transport equation shows that the vortex stretching term plays a dominant role in the spatial evolution of TLV,while the viscous diffusion term plays a minimal role.

关 键 词：轴流泵 叶顶泄漏流 反向发电 叶顶间隙 

分 类 号：TH312[机械工程—机械制造及自动化]