基于大涡模拟的射流式离心泵射流器内部的流动特性

doi:10.3969/j.issn.1674-8530.16.0060

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Abstract In this paper, large eddy simulation with dynamic sub-grid stress model is adopted to study on fluid dynamics in the jet nozzle of a self-pariming centrifugal pump to examine the effects of transient pressure fluctuation on incipient cavitation characteristics in the pump and the reslts are compared with those obtained by means of the SST k-ω turbulence model. The results show that the time-averaged SST k-ω model cannot adequately simulate the pressure pulsation features at the throat of the nozzle, showing a constant value over time basically. However, the large eddy simulation with dynamic sub-grid stress model is able to get a variable pressure pulsation profil over time, but also the profile agrees well with experimental results, reflecting the actual situation of pressure pulsation. A vrotex ring is formed downstrea the jet in the nozzle, which is generated in the shear layer between the the suctioned fluid with low velocity and the driving fluid of high velocity. The instable vortex induces a voilent pressure fluctuation. A twisted vortex ring propagates downsteam and absorbs the kinetic enegy of the fluid with high velocity. The ring collapses at the thoat to produce the largest prssure pulsation amplide. As a result of this, cavitation is mostly prone to occur there. 

Key words： flow-ejecting centrifugal pump jet aerator pressure distribution cavitation large-eddy simulation

Received: 19 March 2016

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	LI Gui-Dong-
	WANG Yang-
	YANG Xue-Ming-
	ZHAO Li-Feng-
	WU Wen-
	HU Ri-Xin-

Cite this article:

LI Gui-Dong-,WANG Yang-,YANG Xue-Ming-等. Features of internal flow in jet nozzle of self-priming centrifugal pump based on large eddy simulation[J]. Journal of Drainage and Irrigation Machinery Engin, 2017, 35(5): 369-374.

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http://zzs.ujs.edu.cn/pgjx/EN/10.3969/j.issn.1674-8530.16.0060 OR http://zzs.ujs.edu.cn/pgjx/EN/Y2017/V35/I5/369

[1]顾磊,张景松,杨春敏. 汽蚀工况液体射流泵的试验研究[J]. 流体机械,2006,34(2):7-9.
　　GU Lei, ZHANG Jingsong, YANG Chunmin. Experiment on the liquid jet pump in cavitation[J]. Fuild machinery, 2006, 34(2): 7-9.(in Chinese)
[2]龙新平,姚昊,赵建福. 射流泵极限工况下空化流动[J]. 机械工程学报,2009,45(12):59-64.
　　LONG Xinping, YAO Hao, ZHAO Jianfu. The mechani-cal of cavitation flow in jet pump under the limiting condition[J]. Chinese journal of mechanical engineering,2009,45(12): 59-64.(in Chinese)
[3]李贵东,王洋,曹璞钰,等. 射流式离心泵非设计工况下内部流动研究[J]. 农业机械学报,2015,46(8):48-53.
　　LI Guidong, WANG Yang, CAO Puyu, et al. Internal flow of flow-ejecting centrifugal pump under off-design conditions[J]. Transactions of the CSAM, 2015, 46(8): 48-53.(in Chinese)
[4]YAMAZAKI Y, YAMAZAKI A, NARABAYASHI T, et al. Studies on mixing process and performance improvement of jet pump: effects of nozzle and throat shapes[J]. Transactions of the Japan society of mechanical engineers(series B), 2005, 701(71):147-153.
[5]YAMAZAKI Y, YAMAZAKI A, NARABAYASHI T, et al. Studies on mixing process and performance improvement of jet pumps[J]. Journal of fluid science & technology, 2007, 2(1):238-247.
[6]JAHNKE S, KORNEV N, TKATCHENKO I, et al.Numerical study of influence of different parameters on mixi-ng in a coaxial jet mixer using LES[J]. Heat & mass transfer, 2005, 41(5):471-481.
[7]MALLELA R, CHATTERJEE D. Numerical investigation of the effect of geometry on the performance of a jet pump[J]. Journal of mechanical engineering science, 2011, 225(7): 1614-1625.
[8]吕忠斌,王洋,刘洁琼,等. 射流泵喷嘴收缩角的取值[J]. 江苏大学学报(自然科学版),2015,36(3):281-287.
　　LYU Zhongbin, WANG Yang, LIU Jieqiong, et al. Value of nozzle falloff angle of jet pump[J]. Journal of Jiangsu University(natural science edition), 2015, 36(3): 281-287.(in Chinese)
[9]龙新平,何培杰. 射流泵汽蚀问题研究综述[J]. 水泵技术,2003(4):33-38.
　　LONG Xinping, HE Peijie. Overview of cavitation in jet pump[J]. Pump technology, 2003(4): 33-38.(in Chinese)
[10]龙新平,程茜,韩宁. 射流泵空化影响因素的数值分析[J]. 应用基础与工程科学学报,2009,17(3):461-469.
　　LONG Xinping, CHENG Qian, HAN Ning. Numerical analysis of the influence factors of the jet pump cavitation[J]. Application foundation and engineering science journal, 2009, 17(3): 461-469.(in Chinese)
[11]刘晖霞. 环形射流泵产生空化的机理及其改善的研究[D]. 重庆:重庆大学,2007.
[12]杨雪龙. 环形射流泵内部流动机理及结构优化研究[D]. 武汉:武汉大学,2014.
[13]薛梅新,朴英. 高压喷嘴空化初生的大涡模拟[J]. 工程力学,2013,30(4):417-422.
　　XUE Meixin, PU Ying. Large eddy simulation of cavitation inception at high pressure nozzle[J]. Engineering mechanics, 2013, 30(4):417-422.(in Chinese)
[14]周凌九,袁玲丽. 射流泵内部流动计算中不同湍流模拟方法的比较[J]. 排灌机械工程学报,2013,31(1):25-30.
　　ZHOU Lingjiu, YUAN Lingli. Comparison of internal flows in jet pump predicted by various turbulence models[J]. Journal of drainage and irrigation machinery engineering, 2013, 31(1): 25-30.(in Chinese)
[15]BYSKOV R K, JACOBSEN C B, PEDERSEN N, et al. Flow in a centrifugal pump impeller at design and off-design conditions——Part II: large eddy simulations[J]. Journal of fluids engineering, 2003, 125(1): 73-83.
[16]GULEREN K M, TURAN A, PINARBASI A. Large-eddy simulation of the flow in a low-speed centrifugal compressor[J]. International journal for numerical methods in fluids, 2008, 56(8): 1271-1280.
[17]ROOHI E, ZAHIRI A P, PASSANDIDEH F M. Numerical simulation of cavitation around a two-dimensional hydrofoil using VOF method and LES turbulence model[J]. Applied mathematical modelling, 2013, 37(9): 6469-6488.