摘要
混流式水轮机的泥沙磨损破坏是含沙河流水电开发中的关键难题。泥沙特性及流态是影响磨损破坏的核心因素,如何有效控制流态进而改变颗粒运动是当前研究的重要内容。本文基于叶片设计理论,通过优化叶片进口偏转角及安放角的分布降低叶片磨损程度,进而提出抗磨损叶片的设计方案。研究结果表明,两种角度分布规律的调整均能显著降低叶片的磨损强度和范围,同时保证了水轮机的运行效率,但增加了下环磨损。叶片进口偏转角θ*0=0.2和叶片安放角关系幂指数x=3的组合方案下,叶片磨损率降低程度最高为71%。这种现象的主要原因是角度变化影响了叶道涡,进而改变了颗粒轨迹,导致颗粒在叶片和下环的打击位置发生变化,最终影响不同区域的磨损分布。综合考虑,通过适度牺牲下环保护叶片的设计方案可以有效增加叶片的使用寿命,降低维修成本和提高维修便利性。
Erosive damage of Francis tubine operated along the sand-laden rivers is the key point in hydropower development.Sand and flow fluid are the main factors,and methods to improve the flow field are the main content.Adapting the angle along the blade leading edge and the installation angle is proposed based on the design theory of turbine blades to reshape the damage distribution.The results show that reasonable design for two angles can reduce blade damage,and ensure operating efficiency,but increase shroud damage.Under the combination of the angle along the blade leading edge 0"=0.2 and the installation angle index x=3,the blade damage decreases by a maxi-mum of 71%.The reason is that due to angle adjustments,the vortex alters and the hitting location deviates,re-sulting in erosive wear in different regions.Finally,the design optimization of protecting the blades by sacrificing the shroud is more effective in reducing maintenance costs and increasing m aintenance convenience.
作者
钱忠东
钟琴琴
曾心成
郭志伟
QIAN Zhongdong;ZHONG Qinqin;ZENG Xincheng;GUO Zhiwei(State Key Laboratory of Water Resources Engineering and Management,W uhan University,Wuhan 430072,China)
出处
《水利学报》
北大核心
2025年第4期433-444,共12页
Journal of Hydraulic Engineering
基金
国家自然科学基金项目(52279090)。
关键词
混流式水轮机
泥沙磨损
叶片进口偏转角
叶片安放角
叶道涡
Francis turbine
erosive damage
angle along the blade leading edge
installation angle
interblade vortex
作者简介
钱忠东(1976-),博士,教授,主要从事水力机械多相流研究。E-mail:zdqian@whu.edu.cn;通信作者:郭志伟(1985-),博士,副教授,主要从事水力机械泥沙磨损研究。E-mail:Guozw1985@outlook.com。
