Matching characteristic between impeller and bowl diffuser in multi-stage centrifugal pump
WANG Kai1, WANG Wenbo2, LIU Houlin1, XIA Chen1
1.National Research Center of Pumps, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 2.School of Energy and Power Engineering, Xi′an Jiaotong University, Xi′an, Shaanxi 710049, China
Abstract：The flow field in a three-stage centrifugal pump was simulated by using CFX software based on the standard k-ε turbulence model, the predicted performance curves were compared with the measurements, and good agreement was showed. After a further analysis on the flow details, however, a larger hydraulic loss has occurred in the gap between the impeller and the bowl diffuser as well as in the diffuser itself. In order to reduce the hydraulic loss and improve the matching characteristic of the diffuser to the impeller, four diffusers with different inlet structures are designed. The steady flow in the three-stage pumps with these diffusers is simulated at the design point, and the pump performance, flow pattern and the pressure distribution over the diffuser vane pressure side are analysed. The results show that the diffuser with untwisted inlet and in parallel with the impeller outlet has the best hydraulic performance. The diffuser with twisted inlet results in an increased impeller head, but the hydraulic loss in the gap between the impeller and the diffuser rises, and the pressure at the inlet of diffuser becomes instable. The diffuser with inlet edge in parallel with the impeller outlet can reduce the inside loss to improve the hydraulic performance. Even though the diffuser with inlet edge in parallel with the pump shaft can compromise the interference with the impeller to increase the impeller hydraulic performance, the hydraulic loss in the gap is increased.
王凯, 王文博, 刘厚林, 夏晨. 多级离心泵叶轮与导叶的匹配特性[J]. 排灌机械工程学报, 2016, 34(5): 392-398.
WANG Kai, WANG Wenbo, LIU Houlin, XIA Chen. Matching characteristic between impeller and bowl diffuser in multi-stage centrifugal pump. Journal of Drainage and Irrigation Machinery Engin, 2016, 34(5): 392-398.
[1]关醒凡.现代泵理论与设计[M]. 北京:中国宇航出版社,2011.[2]BONAIUTI D,ZANGENEH M,AARTOJARVI R,et al.Parametric design of a water-jet pump by means of inverse design,CFD calculations and experimental analyses[J].Journal of fluids engineering,2010,132(3):1-5.[3]马文昌,曹辉,宋少雷. 基于速度矩分布的喷水推进泵反设计及抗汽蚀性能分析[J]. 江苏科技大学学报(自然科学版),2013,27(3):219-223. MA Wenchang, CAO Hui, SONG Shaolei. Inverse design of water jet pump and anti-cavitation analysis[J]. Journal of Jiangsu University of Science and Technology(natural science edition), 2013, 27(3): 219-223.(in Chinese)[4]KIM Sung,CHOI Young-Seok,LEE Kyoung-Yong,et al. Design optimization of mixed-flow pump in a fixed meridional shape[J].International journal of fluid machinery and systems,2011,4(1):14-24.[5]KIM Jin-Hyuk,KIM Kwang-Yong. Optimization of vane diffuser in a mix-flow pump for high efficiency design[J].International journal of fluid machinery and systems,2011,4(1):172-178.[6]FERRO L M C, GATO L M C, FALCAO A F O. Design and experimental validation of the inlet guide vane system of a mini hydraulic bulb-turbine[J]. Renewable energy,2010,35:1920-1928.[7]WANG Pengfei, RUAN Xiaodong, ZOU Jun, et al. Medial axis transform method for shape design of hub and shroud contours of impellers[J]. Journal of fluids engineering, 2011, 133: 034502.[8]孔繁余,王婷,张洪利. 基于流场数值模拟的多级泵转子动力学分析[J]. 江苏大学学报(自然科学版),2011,32(5):516-521. KONG Fanyu, WANG Ting, ZHANG Hongli. Rotor dynamic analysis of multistage pump based on numerical simulation of flow field[J]. Journal of Jiangsu University(natural science edition), 2011, 32(5): 516-521.(in Chinese)[9]平仕良,吴大转,谭善光,等. 大功率高压多级离心转子动力学分析[J]. 工程热物理学报,2010,31(7):1135-1138. PING Shiliang, WU Dazhuan, TAN Shanguang, et al. Rotor dynamics analysis on high-power high-pressure multi-stage centrifugal pump[J]. Journal of engineering thermophysics, 2010, 31(7): 1135-1138.(in Chinese)[10]马旭丹,吴大转,王乐勤. 多级离心泵轴向力平衡装置的设计与分析[J]. 农业工程学报,2010,26(8):108-122. MA Xudan, WU Dazhuan, WANG Leqin. Design and analysis of an axial thrust balancing device for multistage centrifugal pumps[J]. Transactions of the CSAE, 2010, 26(8): 108-122.(in Chinese) [11]胡敬宁,肖霞萍,叶晓琰,等. 反渗透海水淡化提升泵轴向力和径向力平衡的研究[J]. 流体机械,2009,37(10):19-23. HU Jingning, XIAO Xiaping, YE Xiaoyan, et al. Research on axial force and radial force balance of lilt pump for reverse osmosis seawater desalination[J]. Fluid machinery, 2009, 37(10): 19-23.[12]TUSHAR G,DANIEL J D,RAPHAEL T H. Improving the hydrodynamic performance of diffuser vanes via shape optimization [J]. Computers & fluids,2008,37(10):705-723.[13]汪家琼,孔繁余. 多级离心泵叶轮与导叶水力性能优化研究[J]. 华中科技大学学报(自然科学版),2013,41(3):92-96. WANG Jiaqiong, KONG Fanyu. Hydraulic performance optimization study on impeller and diffuser of multi-stage centrifugal pump[J]. Journal of Huazhong University of Science and Technology(natural science edition), 2013, 41(3): 92-96.(in Chinese)[14]薛睿,李家文,唐飞. 多级泵级间导叶的优化与数值仿真[J]. 火箭推进,2011,37(5):24-29,68. XUE Rui, LI Jiawen, TANG Fei. Optimization and numerical simulation for interstage crossover of multistage pump[J]. Journal of rocket propulsion, 2011, 37(5): 24-29, 68.(in Chinese)[15]钱涵欣,何成连. 固定导叶安放角及轮缘间隙对混流泵性能影响的研究[J]. 水力发电,1997,28(4):36-38. QIAN Hanxin, HE Liancheng. Influence on the mixed flow pump performance and fixed guide vane angle and the flange clearance [J]. Water power, 1997, 28(4): 36-38.(in Chinese)
