Analysis of flow in liquid jet pump—PartⅡ:Determination of dimensionless coefficients in theoretical model
WANG Yu-Chuan, CAO Shu-Liang, GAO Chuan-Chang, WANG Song-Lin
(1. State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing 100084, China; 2. School of Electric Power, North China University of Water Resources and Electric Power, Zhengzhou, Henan 450011, China; 3. School of Water Conservancy, North China University of Water Resources and Electric Power, Zhengzhou, Henan 450011, China)
Abstract:The relations of dimensionless coefficients, geometry parameters of crosssection and flow variables have been derived in a theoretical model of jet pumps. Those coefficients were determined by using numerical simulation of flow in the pump, and then their relationships with flow ratio were analyzed. It was indicted that the reaction force distribution coefficient c1 is nearly equal to the suction area ratio c at the best efficiency point; at the other flow conditions, however, two coefficients show significant difference. In fact, replacing c1 with c doesn′t cause a remarked error in theoretical prediction results. When the working fluid velocity keeps to be constant, the momentum correction coefficient k1 is independent of flow ratio, thus can be treated as a constant; the coefficient k2 shows a hyperbolic function against flow ratio, and asymptotically approaches to 1 as the flow ratio increases. The nozzle discharge coefficient 1 and suction chamber discharge coefficient 4 are constant in all the working conditions. The uniformity of velocity distribution in the diffuser inlet has a great influence on the diffuser velocity coefficient 3. The velocity correction coefficient at the throat 2 and the velocity correction coefficient 5 at the inlet to the nozzle of suction chamber decrease linearly as the flow ratio increases. They affect the results of theoretical model remarkably. The theoretical predictions show good agreement with the experiment results, confirming that the method proposed for determining the dimensionless coefficients is feasible and the model is reliable.
王玉川, 曹树良, 高传昌, 王松林. 液体射流泵内部流动分析:Ⅱ理论计算参数确定[J]. 排灌机械工程学报, 2013, 31(1): 1-6.
WANG Yu-Chuan, CAO Shu-Liang, GAO Chuan-Chang, WANG Song-Lin. Analysis of flow in liquid jet pump—PartⅡ:Determination of dimensionless coefficients in theoretical model. Journal of Drainage and Irrigation Machinery Engin, 2013, 31(1): 1-6.
[1]陆宏圻.喷射技术理论及应用[M]. 武汉:武汉大学出版社,2004.[2]Winoto S H, Li H, Shah D A. Efficiency of jet pump[J]. Journal of Hydraulic Engineering, 2000, 126(2): 150-156.[3]何培杰,龙新平,梁爱国,等. 射流泵流场的PIV测量[J]. 水科学进展,2004, 15(3): 296-299.He Peijie, Long Xinping, Liang Aiguo, et al. PIV measurement of flow field in jet pump [J]. Advances in Water Science, 2004, 15(3): 296-299. (in Chinese)[4]龙新平,陈茜,韩宁,等. 射流泵最佳喉嘴距的数值模拟[J]. 核动力工程,2008,29(1): 35-38.Long Xinping, Chen Qian, Han Ning, et al. Numerical simulation of optimal nozzletothroat clearance of jet pump[J]. Nuclear Power Engineering, 2008, 29(1):35-38. (in Chinese)[5]龙新平,鄢恒飞,张松艳,等. 喉管长度对环形射流泵性能影响的数值模拟[J]. 排灌机械工程学报,2010, 28(3): 198-201.Long Xinping, Yan Hengfei, Zhang Songyan, et al. Numerical simulation for influence of throat length on annular jet pump performance [J]. Journal of Drainage and Irrigation Machinery Engineering, 2010, 28(3):198-201. (in Chinese)[6]Narabayashi T, Yamazaki Y, Kobayshi H,et al. Flow analysis for single and multinozzle jet pump [J]. Fluids and Thermal Engineering, 2006, 49(4):933-940.[7]Song Xueguan, Park J H, Kim S G, et al. Performance comparison and erosion prediction of jet pumps by using a numerical method [J]. Mathematical and Computer Modeling, 2013, 57(1/2): 245-253.[8]Yamazaki Y, Yamazaki A, Narabayashi T, et al. Studies on mixing process and performance improvement of jet pumps [J]. Journal of Fluid Science and Technology, 2007, 2(1):238-247.[9]王松林,王玉川,桂绍波,等. 液体射流泵内部流动分析:Ⅰ试验与三维数值模拟[J]. 排灌机械工程学报,2012,30(6):655-659.Wang Songlin, Wang Yuchuan, Gui Shaobo,et al. Analysis of flow in liquid jet pump-Part Ⅰ:Experiment and threedimensional numerical simulation[J]. Journal of Drainage and Irrigation Machinery Engineering,2012,30(6):655-659. (in Chinese)[10]高传昌,王玉川,陈豪,等.脉冲液-气射流泵基本性能试验[J]. 核动力工程,2010,31(4): 133-137.Gao Chuanchang, Wang Yuchuan, Chen Hao, et al. Experiment study on fundamental performance of pulsed liquid gas jet pump[J]. Nuclear Power Engineering, 2010,31(4): 133-137. (in Chinese)[11]Yamazaki Y, Nakayama T, Narabayashi T,et al. Effect of surface roughness on jet pump performance [J]. Fluids and Thermal Engineering, 2006, 49(4):928-932.