低比转数离心泵驼峰现象的CFD分析CFD Research on Hump Phenomenon of Low Specific Speed Centrifugal Pump
马皓晨,丁荣,杨东升
MA Hao-chen,DING Rong,YANG Dong-sheng
摘要(Abstract):
为揭示低比转数离心泵性能曲线产生驼峰现象的内流机理,采用RANS方法算法对一低比转数离心泵2个方案(有驼峰和无驼峰)下的内部进行了全流场CFD计算,重点分析了驼峰现象产生时2个方案内部流动结构的差异。结果表明:性能曲线出现驼峰时,2个方案的靠近蜗壳隔舌的叶轮流道内的流动结构差异最为明显;该流道内叶片压力面的低速区会明显增大并伴有漩涡流动;该流道进口也会出现明显的漩涡流动引起进口冲击损失增加;同时该流道出口的"射流-尾迹"现象也会突变,引起出口(混合)水力损失增加。因此这些损失的增大是引起驼峰现象的重要原因。
In order to study the hump of pump performance curve in low specific speed centrifugal pumps,using RANS method algorithm to CFD calculations of internal full flow of low specific speed centrifugal pump in two schemes( has a hump and without the hump) to calculate and analysis. Differences of the internal flow structure are emphatically analyzed in two schemes when hump phenomenon occurs. The results show that the performance curve appeared hump,the flow structure differences of the impeller flow passage near the volute tongue in two programs are the most obvious. Low speed area in the pressure side of the impeller blade in the passage can significantly increase accompanied by vortex flow. The flow of imports also appear obvious vortex flow,losses increased by the impact of the vortex flow. Meanwhile,the " jet-wake" phenomenon of the channel outlet also mutate,causing exports hydraulic losses increase. Therefore,the increase of these losses is the significant cause of hump phenomenon.
关键词(KeyWords):
低比数离心泵;驼峰现象;CFD;水力损失
low specific speed centrifugal pump;hump phenomenon;computational fluid dynamics;hydraulic losses
基金项目(Foundation): 国家自然科学基金资助项目(51109095);国家自然科学基金资助项目(51079062)
作者(Author):
马皓晨,丁荣,杨东升
MA Hao-chen,DING Rong,YANG Dong-sheng
参考文献(References):
- [1]袁寿其.低比速离心泵理论与设计[M].北京:机械工业出版社,1997.
- [2]牟介刚,张生昌,郑水华,等.离心泵性能曲线产生驼峰的机理及消除措施[J].农业机械学报,2006,37(4):56-59.
- [3]杨琳.消除离心泵特性曲线的驼峰[J].新疆大学学报(自然科学版),2002,19(6):32-34.
- [4]韩建宇.低比速离心泵性能曲线驼峰问题的研讨[J].水泵技术,2004,(4):24-27.
- [5]李学兰.低比转数多级泵驼峰和效率问题探讨[J].水泵技术,1996,(2):30-32.
- [6]严敬,潘光玉,阚能琪,等.低比转速叶轮叶片数的选择准则[J].排灌机械,2008,26(1):18-20.
- [7]牟介刚,王乐勤.离心泵性能曲线驼峰判据的探讨[J].农业机械学报,2004,35(4):74-76.
- [8]王志坚,佟亮,李璐璐,等.基于CFD的离心泵内部三维流动数值模拟和性能预测[J].流体机械,2012,40(6):22-26.
- [9]黄思,管俊.基于空化模型的多级离心泵汽蚀性能分析[J].流体机械,2011,39(1):35-38.
- [10]李辰光,王福军,许建中,等.两级双吸离心泵压力脉动特性[J].农业机械学报,2011,42(7):41-49.
- [11]王福军.计算流体动力学分析——CFD软件原理与应用[M].北京:清华大学出版社,2004.
- [12]Westre R W,Broersma L.PIV measurements and CFD computations of secondary flow in a centrefugal pump impeller[J].Journal of Fluids Engineering,2010,132(6):1-8.