低比转数离心泵驼峰现象的PIV测试  

PIV test on hump phenomenon of low specific speed centrifugal pumps

作　　者：马皓晨[1] 丁荣[2] 杨东升[3] 

机构地区：[1]江苏大学机械学院,江苏镇江212013 [2]江苏大学流体机械工程技术研究中心,江苏镇江212013 [3]中国科学院上海应用物理研究所,上海201800

出　　处：《排灌机械工程学报》2013年第12期1056-1060,共5页Journal of Drainage and Irrigation Machinery Engineering

基　　金：国家自然科学基金资助项目(51109095;51079062)

摘　　要：低比转数离心泵性能曲线驼峰问题严重影响泵的运行稳定性,但至今尚未得到很好的解决.为了揭示低比转数离心泵驼峰现象的内流机理,首先根据一比转数为73的离心泵水力设计要求设计了2种水力模型,其中方案1有驼峰,方案2无驼峰,并对2种方案进行了能量性能试验从而验证水力设计的正确性;接着采用粒子图像测量技术对2个方案的内部流动进行了多工况测试与分析.结果表明:当性能曲线出现驼峰时,叶片压力面处的低速区迅速增大,且在多个流道的叶片压力面出现了较大的旋涡,引起叶轮内流态恶化;叶轮出口与蜗壳基圆间隙之间的回流进一步增大;叶轮出口绝对速度与蜗壳基圆处流速差值也明显增加,导致了泵内冲击损失增大从而引起性能曲线的驼峰现象.研究成果能够为控制低比转数离心泵驼峰现象提供理论参考.The hump in performance curve of low specific speed centrifugal pumps affects the reliability obviously,which is still not solved today.In order to study inner flow mechanism of the hump,two hydraulic models are designed according to the same design requirements,in which scheme 1 has hump phenomenon and scheme 2 has no hump phenomenon.The performance of the two models is tested to validate the design.Then the internal flow of two model pumps are tested and analyzed by particle image velocimetry(PIV) system.The results show when performance curve appears hump,low speed area at the pressure side of the impeller blade increases rapidly,and vortex appeared at blade pressure surface of several channels.In the gap between impeller outlet and volute base circle,the flow rate of recirculation increases.The velocity difference between the impeller outlet and base circle of the volute also increases significantly,which results in increase of the hydraulic loss in the pump and causes hump phenomenon of the performance curve.The research results of the study can provide theoretical references to control the hump phenomenon of low specific speed centrifugal pumps.

关 键 词：低比转数离心泵 驼峰现象 PIV 内部流动 水力模型 

分 类 号：TH311[机械工程—机械制造及自动化] S277.9[农业科学—农业水土工程]