水力发电学报2026，Vol.45Issue(9)：50-59,10.DOI:10.11660/slfdxb.20260905
均压管节流装置对间隙流动及顶盖补气的影响
Effect of pressure equalizing tube throttling device on gap flow and head cover air admission
摘要
Abstract
To improve the behavior of flows in the runner-headcover gap,this paper describes a novel throttling device installed in the pressure equalizing pipe of a pump-turbine unit,focusing on its effects on flow regime and air admission in the gap.We conduct numerical simulations of the runner-head cover gap,using the CFD method,the SST k-ω turbulence model,and the Volume of Fluid(VOF)multiphase flow model.And,in a case study of the Meizhou pumped storage station,throttling orifices with different diameters(relative diameters d/D=0.238,0.298,0.357,0.476)are examined and compared against the case of no installation.Results show a smaller throttling orifice size induces vortices and backflows in the equalizing pipe.The size has a significant influence on the gap leakage flow rate and the axial force on the lower wall,and a considerable effect on the air admission performance;The flow rate,under the condition of d/D≥0.357,is lowered effectively with little impact on the wall force.At d/D=0.476,peak values occur in the total gas volume fraction and the fraction in the outer cavity of the gap,indicating the best air admission effect under this orifice condition.For the study case,we recommend the optimal size of d/D=0.476 based on a comprehensive consideration of the gap flow and air admission performance.Our findings lay a basis for optimizing the structural design of the unit's equalizing pipe and improving the units safe and stable operation.关键词
间隙流动/均压管/泄漏量/轴向力/顶盖补气Key words
gap flow/pressure equalizing pipe/leakage flow rate/axial force/head cover air admission分类
建筑与水利引用本文复制引用
尚凤,陈泓宇,周凌九,李开明,张超..均压管节流装置对间隙流动及顶盖补气的影响[J].水力发电学报,2026,45(9):50-59,10.基金项目
国家自然科学基金面上项目(52479091) （52479091）
