采用Liutex涡识别法的水泵水轮机S区内流特性分析  

Analysis of vortex characteristics in S-shaped region of pump turbine based on Liutex method

作　　者：肖业祥[1,2] 肖微 任绍成[4] 陈柳[4] 刘子实 XIAO Yexiang;XIAO Wei;REN Shaocheng;CHEN Liu;LIU Zishi(State Key Laboratory of Hydroscience and Engineering,Tsinghua University,Beijing 100084,China;Department of Energy and Power Engineering,Tsinghua University,Beijing 100084,China;Pumped-storage Technological&Economic Research Institute State Grid Xinyuan Company LTD,Beijing 100761,China;China Institute of Water Resources and Hydropower Research,Beijing 100048,China)

机构地区：[1]清华大学水圈科学与水利工程全国重点实验室,北京100084 [2]清华大学能源与动力工程系,北京100084 [3]国网新源控股有限公司抽水蓄能技术经济研究院,北京100761 [4]中国水利水电科学研究院,北京100048

出　　处：《水力发电学报》2025年第1期135-142,共8页Journal of Hydroelectric Engineering

基　　金：国家电网有限公司总部管理科技项目资助(5419-202243054A-1-1-ZN)。

摘　　要：为探究水泵水轮机S特性出现的原因,首先将数值预测的特性曲线与模型试验进行了对比分析,然后基于Liutex涡识别法分析了各过流部件在S特性区的流动和涡旋分布情况,探讨了S区相同转速不同流量工况下的内部流动变化规律。分析发现:相同转速下水轮机工况蜗壳内的流动稳定性较好,几乎没有涡旋出现;导叶和转轮域内流动较为均匀,只在无叶区分布有少量涡旋,水流稳定性较好。制动工况蜗壳内流动开始变得较不稳定,涡旋集中分布在蜗壳出口环面上,容易形成涡团阻碍水流进入固定导叶;在导叶叶栅间存在明显的涡旋和回流现象,导叶和转轮的叶栅堵塞较为严重。反水泵工况在尾水管出口出现螺旋状回流,导致流入转轮的水流发生旋转失速等不稳定现象;水流一部分在活动导叶进水边沿圆周方向高速流动,存在严重的流动分离现象,涡旋分布最密集,由于无叶区内存在压力突变区,导致涡旋几乎占据整个流道。To explore the cause of the S-shaped region of a revisable pump turbine,its full characteristics are compared with model test results.Then,we analyze the flow and vortex distribution in each of its flow components in this region using the Liutex vortex identification method,and reveal the variations in the corresponding internal flows with flow rate.We find that under the same rotational speed,flow stability in the volute is better and almost no vortices occur there.In the guide vane and runner sections,the flow is relatively uniform and has a good stability;only a small number of vortices are distributed in the vaneless section.Under the braking condition,the flow in the volute becomes more unstable and the vortices is concentrated on its outlet ring,where a large vortex is easy to develop and block the flow into the fixed guide vanes.Evident vortices and backflows are observed in the guide vane spaces,and cascade blockage is more severe in the guide vane and runner sections.In the reverse pump condition,spiral backflow occurs at the outlet of the draft tube,resulting in unsteady phenomena such as the rotating stall of water flow into the runner.Near the inlet edge of the guide vanes,part of the flow runs at a high velocity along its circumferential direction,and severe flow separation is generated with the densest vortices gathering around.In the vaneless section where the zones of great pressure gradient are possible,the vortices occupy nearly the whole flow channel.This is an operating region where the unit is easy to suffer large pressure fluctuations and even the runner could be damaged,and longtime operation in this region must be avoided.

关 键 词：可逆式水泵水轮机 Liutex涡识别法 S特性区 涡旋特征 

分 类 号：TK734[交通运输工程—轮机工程]