水力发电学报2026，Vol.45Issue(1)：1-10,10.DOI:10.11660/slfdxb.20260101
上止漏环间隙尺寸对水泵水轮机运行稳定性的影响分析
Analysis on influence of upper seal clearance width on operational stability of pump-turbines
摘要
Abstract
This study develops a new three-dimensional multi-scale full-passage model of a pump-turbine that incorporates its millimeter-level sealing clearances,exploring the influence mechanism of its upper clearance width on operational stability.This study conducts numerical simulations of the flows for the five different dimensionless clearance widths for 50%,80%,and 100%load conditions,focusing on comparison of the characteristics of flow structures,pressure pulsation,and hydrodynamic performance.It was found that wider clearances intensify secondary flow leakage vortices on the pressure suction side of the runner's upper crown.This leads to increasing fluctuations in the radial force on the top cover and higher pressure-pulsating amplitudes,which may rise by up to 15%in the extreme conditions.However,wider clearances reduce the axial thrust of the flow,with a reduction of 0.8%observed for high-load conditions.Conversely,narrower clearances help suppress leakage vortices and stabilize the flow,but result in an increase in the axial thrust at an minimal increment though-less than 0.1%for the full load conditions.Clearance adjustment significantly affects performance for high-load conditions,whereas for medium-or low-load conditions,the strengthening of blade passage vortices tends to induce hydraulic instability.This study has elucidated the mechanism of correlation between clearance widths and dynamic loads,and given a recommendation for engineering application-a moderate reduction of the upper seal clearance in the 0-20%range for enhanced operational stability under the rated conditions.This would lay a basis for optimizing sealing design,balancing axial thrust,and controlling vibration.关键词
水泵水轮机/上止漏环间隙/运行稳定性/压力脉动/轴向水推力/泄漏涡Key words
pump-turbine/upper seal clearance/operational stability/pressure pulsation/axial hydraulic thrust/leakage vortex分类
能源科技引用本文复制引用
杜贻钊,李晓波,汤嘉伟,于韵宽,郑源,阚阚..上止漏环间隙尺寸对水泵水轮机运行稳定性的影响分析[J].水力发电学报,2026,45(1):1-10,10.基金项目
国家自然科学基金面上项目(52379086 （）
52271275) （）
江苏省创新支撑计划国际科技合作项目(BZ2023047) （BZ2023047）
