混流式水轮机大开度下的转轮抗泥沙磨损设计  

Erosion Wear Resistant Design of Francis Turbine Runner Under Large Opening Conditions

作　　者：曾心成 郭志伟[1] 钱忠东[1] ZENG Xin-cheng;GUO Zhi-wei;QIAN Zhong-dong(State Key Laboratory of Water Resources and Hydropower Engineering Science,Wuhan University,Wuhan 430072,Hubei Province,China)

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072

出　　处：《中国农村水利水电》2023年第4期302-308,共7页China Rural Water and Hydropower

基　　金：国家自然科学基金资助项目(52279090)。

摘　　要：发源于喜马拉雅山脉的河流均含有大量泥沙,不可避免对沿岸的水电站造成泥沙磨损破坏,严重影响水轮机寿命,危害水电站安全稳定运行。以尼泊尔长期处于大开度运行工况Jhimruk水电站的混流式水轮机转轮设计为基础,采用数值模拟手段,针对转轮进口,开展水轮机转轮抗磨损优化设计方案研究,重点分析不同方案下水轮机的外特性和转轮磨损特性。结果表明:3种设计方案均在不降低水轮机效率的情况下,降低了叶片的平均磨损率。通过改变叶片表面的水流流动方向,可以影响流道内的漩涡结构,削弱叶片压力面的横流,进而降低转轮的平均磨损。在当前的研究方案中,进口形状符合线性函数的方案二抗磨效果最好,磨损率可以降低35%。研究成果可为长期处于大开度下运行的水轮机抗磨损优化设计提供重要参考。Rivers originating from the Himalaya contain a large amount of sediment,which inevitably causes erosion wear and damage to the hydropower plants,seriously decrease the life time of the turbines and operational stability of the hydropower plants.A Francis turbine run⁃ner of Jhimruk Hydropower Plant in Nepal,which has been operating at large opening for a long time,is used in this study.By combining nu⁃merical simulation and wear-resistant optimization design of the turbine runner,its performance and erosion characteristics are analyzed.The results show that the three designing schemes reduce the average erosion rate of the blades without reducing the efficiency of the turbine.By changing the flow direction on the blade surface,the vortex pattern in the passage is changed,which weakens the cross flow on the pres⁃sure side of the blade,so the erosion rate of the runner is reduced.In this research,the inlet shape conforming to the linear function(schemeⅡ)is the best for wear resistance,by which the erosion rate is reduced by 35%.The research results provide a reference for the wear-resis⁃tant design of hydraulic turbines operating at large opening conditions.

关 键 词：混流式水轮机 泥沙磨损 转轮设计 数值模拟 

分 类 号：TK733[交通运输工程—轮机工程]