正导叶进出口角对多级液力透平性能的影响  

Effect of inlet and outlet angles of positive guide vanes on performance of multistage hydraulic turbine

作　　者：苗森春 张佳伟 王晓晖[1] 史凤霞[1] 杨军虎[1] MIAO Senchun;ZHANG Jiawei;WANG Xiaohui;SHI Fengxia;YANG Junhu(College of Energy and Power Engineering,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]兰州理工大学能源与动力工程学院,兰州730050

出　　处：《水力发电学报》2023年第3期60-69,共10页Journal of Hydroelectric Engineering

基　　金：国家自然科学基金项目(52169019);甘肃省自然科学基金项目(20JR10RA174);流体及动力机械教育部重点实验室(西华大学)开放基金(LTDL2020-007)。

摘　　要：为揭示正导叶进出口角对多级液力透平性能的影响,以一台3级离心泵作液力透平为研究对象,利用速度矩相等并根据叶轮和反导叶几何参数推导出正导叶进出口角,设计出推导后的三种导叶模型,通过计算流体力学软件CFX对初始方案和三种新方案进行数值模拟并对比分析。结果表明:三种新方案在各个流量工况下效率均有明显提高,且高效运行范围变宽,其中新方案中方案C液力透平的性能最佳,在最优工况下效率提升了2.15%;内流方面,新方案下的多级液力透平在正导叶与叶轮之间的压力分布更加均匀,各级叶轮叶片进口附近的漩涡区域变小,同时对于进口处较高的湍动能区域也有明显减弱。上述研究可为今后多级液力透平导叶设计和优化提供一定参考。To reveal the influence of the inlet and outlet angles of positive guide vanes on the performance of a multistage hydraulic turbine,a three-stage centrifugal pump is examined in this study.These angles are derived analytically from the geometric parameters of the impeller and reverse guide vanes by using the equal velocity moment;three kinds of guide vane models are designed.Then,these three new schemes and the initial scheme are numerically simulated and compared based on the computational fluid dynamics code CFX.The results show that the new schemes significantly improve the efficiency under various flow conditions,and widen the range of high-efficiency operation.Among them,Scheme C of the new designs has the best performance,with an efficiency increase by 2.2%under the optimal operating condition.The new schemes also improve the internal flow state of a multistage hydraulic turbine-more uniform pressure distributions between its positive guide vanes and impeller;smaller vortex area near the inlet of the impeller blades in all 4stages;a significant reduction of the high turbulent kinetic energy area near the inlet.This study would help the design and further optimization of multistage hydraulic turbine guide vanes.

关 键 词：正导叶 多级液力透平 速度矩 数值模拟 湍动能 

分 类 号：TH311[机械工程—机械制造及自动化]