Improved centrifugal pump impeller design in terms of blade wrap and exit angles
WANG Yanyan1,2, ZHAO Weiguo1,2*, HAN Xiangdong1,2, ZHENG Yingjie1,2
1. School of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou, Gansu 730050, China; 2. Key Laboratory of Fluid Machinery and Systems, Gansu Province, Lanzhou, Gansu 730050, China
Abstract Based on computational fluid dynamics(CFD)technology, numerical simulation of flow field in the whole centrifugal pump of KQW250-400 type was performed. At first, the original impeller blade design was altered according to blade design theory, and five impeller models were built by changing the blade wrap angle Φ and the blade exit angle β2. Then, the corresponding hydraulic perfor-mance curves and internal flow fields of the pumps with these different impeller models were obtained numerically. The results indicate that the impeller with blade wrap angle Φ=126° and exit angle β2 = 24° is the optimal and with the best performance, i.e. at the design flow rate Qd=550 m3/h, the calculated head and efficiency are 53.49 m and 87.66%, respectively. Based on the experimental data, the centrifugal pump with the original impeller is subject to a 49.10 m head and a 79.88% efficiency at the flow rate Q=551.381 m3/h in comparison with 51.84 m head and 85.65% efficiency at the flow rate Q=550.823 m3/h for the pump with the optimized impeller. As such the head and efficiency have increased by 2.74 m and 5.77%, respectively, under the design condition; especially, the efficiency curve with the optimized impeller of the centrifugal pump is all above the curve with the original impeller. This suggests that the overall performance of the centrifugal pump has been improved. This outcome is conducive to improving the economic benefits of pump utilization in buildings and subsequently reducing energy consumption.
WANG Yan-Yan-,,ZHAO Wei-Guo- et al. Improved centrifugal pump impeller design in terms of blade wrap and exit angles[J]. Journal of Drainage and Irrigation Machinery Engin, 2019, 37(7): 574-579.
杨乐乐. 离心泵参数化设计与内部流场仿真研究[D]. 秦皇岛: 燕山大学, 2017.
陈冰. 螺旋离心泵的叶片变螺距设计及数值模拟[D]. 兰州: 兰州理工大学, 2008.
MINEMURA K, TOMOMI U. Three dimension calcula-tion of air water two-phase flow in centrifugal pump impeller based on a bubbly flow model with fixed cavity[J]. JSME international journal series B,1994, 37(4):726-735.
WU Yulin. Three-dimension calculation of oil-bubble flows through a centrifugal Pump impeller[C]//Proceedings of the Third International Conference on Pump and Fan. Beijing:Tsinghua University Press, 1998: 526-532.
YANG Hua, GU Chuangang, TANG Fangping, et al. Blade profile optimization for centrifugal pump based on turbulence numerical simulation[J]. Journal of Yang-zhou University(natural science edition),2007,10(3): 41-44.(in Chinese)
XIE Hongtai, DANG Xiaogang. Research on the method of creating multiple curves using Inventor and its application in the manufacture of vane pump[J]. Journal of Shandong University of Technology(natural science edition), 2018, 32(2): 70-73.(in Chinese)
YANG Junhu, BIAN Zhong, ZHONG Cunlin, et al. Method for selecting centrifugal pump impeller outlet angle based on calculation of centrifugal pump impeller′s hydraulic loss[J]. Journal of Xihua University(natural sciences), 2016, 35(3): 89-92,112.(in Chinese)
LI Xueqin,YU Jun, ZHAO Peng, et al. A random fractal model of gas-liquid distribution in multiphase pump[J]. Journal of Guangxi University(natural science edition), 2010,35(5):756-761.(in Chinese)
ZHANG Yining,CAO Weidong,YAO Lingjun,et al. Analysis on pressure fluctuation and radial thrust of centrifugal pump under different blade outlet angle[J]. Fluid machinery, 2017,45(11):34-40.(in Chinese)