Hydrodynamic optimization of large pump installation with two-way channel and experiment
HUANG Liangyong1, WU Zhong1, ZHANG Xiao1, LI Yanjun2
1.Taihu Treatment Project Construction Administration Bureau, Jiangsu Province, Wuxi, Jiangsu 214000, China; 2.National Research Center of Pumps, Jiangsu University, Zhenjiang, Jiangsu 212013, China
Abstract:Large vertical pump installations with two-way channel have been widely used in reversible pumping stations. However, the optimal design theory and method for the two-way channel remain imperfect, causing a low hydraulic efficiency in such an installation. Consequently, a vertical pump installation with two-way channel is studied. By considering the velocity uniformity at the outlet of entry channel and the hydraulic loss across the channel as two objective functions, the open height of the channel is optimized using CFD technique through comparing multiple design cases. It is shown that when the open height is equal to 0.57D the hydraulic loss not only increases less but the outlet velocity uniformity is also the best. The effects of discharge channel height on hydraulic performance of the discharge channel are identified. A bigger discharge channel height can result in a higher discharge velocity and a more significant hydraulic loss. The hydraulic loss across the discharge channel decreases gradually with reducing discharge channel height. However, once the height is below a certain value, the diffusion hydraulic loss in the channel becomes dominant, causing an increasing hydraulic loss. This suggests that there is an optimal discharge channel height at which the minimum hydraulic loss is achievable. In this paper, this height is 0.48D. An optimally selected pump is installed in a pumping installation with the optimized two-way channel, then a hydraulic performance test on the installation is carried out, showing 71.9% hydraulic efficiency at 3.26 m low net head. This two-way channel can provide a reference for installation optimization of the same sort of pumps in the future.
[1]周君亮. 低扬程泵装置原、模型和防止“有害”汽蚀参数换算[J]. 排灌机械工程学报, 2015, 33(3): 185-195. ZHOU Junliang. Conversion of performance for model pump to actual pump and prevention of harmful cavitation[J]. Journal of drainage and irrigation machinery engineering, 2015, 33(3): 185-195.(in Chinese)[2]ZHU Jinmu, ZENG Fanchun. Experimental study on two-way flow passages in pumping system[J]. Journal of mechanical science and technology, 2008, 22(10): 1966-1970.[3]LIU Chao, JIN Yan, ZHOU Jiren, et al. Numerical simulation and experimental study of a two-floor structure pumping system[C]//Proceedings of the ASME Power Conference, 2010: 777-784.[4]朱劲木, 何忠人, 刘德祥, 等. 大型轴流泵站双向出水流道设计及模型试验验证[J]. 武汉大学学报(工学版), 2005, 38(4): 13-16. ZHU Jinmu, HE Zhongren, LIU Dexiang, et al. Design of two way outflow passage for large axial-flow pump station and model experimental verification[J]. Engineering journal of Wuhan University, 2005, 38(4): 13-16.(in Chinese)[5]刘超,金燕,周济人,等. 箱型双向流道轴流泵装置内部流动的数值模拟和试验研究[J].水力发电学报, 2011, 30(4): 192-197. LIU Chao, JIN Yan, ZHOU Jiren, et al. Study of internal flow in cube-type bidirection passages of axial-flow pump system by numerical simulation and experiment[J]. Journal of hydroelectric engineering, 2011, 30(4): 192-197.(in Chinese)[6]陈松山, 葛强, 周正富, 等. 大型泵站双向进水流道三维紊流数值模拟[J]. 江苏大学学报(自然科学版), 2005, 26(2): 102-105. CHEN Songshan, GE Qiang, ZHOU Zhengfu, et al. Numerical simulation of three-dimensional turbulent flow for reversible intake passage in large pumping stations[J]. Journal of Jiangsu University(natural science edition), 2005, 26(2): 102-105.(in Chinese)[7]TANG Xuelin, WANG Fujun, LI Yanjun, et al. Numerical investigation of vortex flows and vortex suppression schemes in a large pumping-station sump[J].Journal of mechanical engineering science, 2011, 225(6): 1459-1480.[8]AHMAD Z, JAIN B, KUMAR S, et al. Rational design of a pump-sump and its model testing[J]. Journal of pipeline systems engineering and practice, 2010, 2(2): 53-63.[9]TOKYAY T E, CONSTANTINESCU S G, ASCE M. Validation of a large-eddy simulation model to simulate flow in pump intakes of realistic geometry[J]. Journal of hydraulic engineering, 2006, 132(12): 1303-1315.[10]杨敏官, 孟宇, 李忠, 等. 轴流泵叶轮导水锥型式设计及其流道水力特性模拟[J]. 农业工程学报, 2015, 31(11): 81-88. YANG Minguan, MENG Yu, LI Zhong, et al. Design of axial-flow impeller guide cone and simulation on hydraulic performance of its passage[J]. Transactions of the CSAE, 2015, 31(11): 81-88.(in Chinese)[11]BI Shude, ZHANG Yonggang, HAN Ning, et al. Numerical simulation on the flow field of inlet structure of Dongsong pumping station[J]. Advances in water resources and hydraulic engineering, 2009: 1731-1736.[12]BI Shude, LIU Meiqing, XU Maosen, et al. Analysis on the flow field of inlet structure of Xingshipo pumping station by CFD method[C]//Proceedings of the International Symposium on Fluid Machinery and Fluid Engineering, 2014.[13]施伟,李彦军,邓东升,等. 肘形进水流道优化设计与数值计算[J].流体机械,2009,37(12):19-22. SHI Wei, LI Yanjun, DENG Dongsheng, et al. Optimum hydraulic design and numerical simulation for elbow inlet passage [J]. Fluid machinery, 2009, 37(12): 19-22.(in Chinese)[14]陶然, 肖若富, 杨魏, 等. 可逆式水泵水轮机泵工况的驼峰特性[J]. 排灌机械工程学报, 2014, 32(11): 927-930. TAO Ran,XIAO Ruofu,YANG Wei, et al. Hump characteristic of reversible pump turbine in pump mode[J]. Journal of drainage and irrigation machinery enginee-ring, 2014, 32(11): 927-930.(in Chinese)[15]QIAN Zhongdong, WANG Yan, HUAI Wenxin, et al. Numerical simulation of water flow in axial flow pump with adjustable guide vanes[J]. Journal of mechanical science and technology, 2010, 24(4): 971-976.[16]WANG Zhengwei, PENG Guangjie, ZHOU Lingjiu, et al. Hydraulic performance of a large slanted axial-flow pump[J]. Engineering computations, 2010, 27(2): 243-256.