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| A study on the turbulent kinetic energy transport characteristics in the impingement region of an impinging jet issuing from a long circular pipe |
| HUANG Haijin1, WANG Duoyin1,2, CHEN Ming1,2, MA Xinlin1 |
1. Key Laboratory of Hydraulic and Waterway Engineering of the Ministry of Education,Chongqing Jiaotong University, Chongqing 400074, China;
2. National Engineering Research Center for Inland Waterway Regulation, Chongqing Jiaotong University, Chongqing 400074, China |
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Abstract To reveal the turbulent kinetic energy transport characteristics in the impingement region of an impinging jet, the turbulent kinetic energy balance in the impingement region with different Reynolds numbers is investigated by using a two-dimensional particle-image velocimetry. The production, the convection, the turbulent diffusion and the viscous diffusion terms of the turbulent kinetic energy transport equation are calculated directly from the measured velocity fields. In addition, the pressure diffusion and the dissipation terms are merged together and calculated as the residual of the turbulent kinetic energy transport equation. The results show that: (1) the direction of the energy transports caused by the convection process is consistent with the mean velocity field. The direction of the energy transports caused by the turbulent diffusion process is oblique to the mean velocity field in the inner shear layer of a free jet, while what is caused by the viscous diffusion process is vertical to the mean velocity field. (2) the turbulent kinetic energy balance in the outer, the middle and the inner layers of the impingement region are quite different. (3) the negative production term in the inner layer of the impingement region is caused by the negative work power generated by the radial and the tangential Reynolds stresses. The turbulent kinetic energy loss caused by the production term is compensated by the pressure diffusion term. (4) the energy carried away from the impingement region in the radial convection process is compensated by the axial convection process. (5) the above physical processes are basically not affected by the Reynolds number. The contribution intensity of each energy balance term to the turbulent kinetic energy, however, is significantly affected by the Reynolds number.
Key words: impinging jet; impingement region; turbulent kinetic energy; transport characteristic; experimental investigation
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Received: 16 December 2021
Published: 28 October 2022
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[1] 吕远征, 夏国栋, 陈永昌. 微尺度方波射流冲击阵列的传热特性研究[J]. 振动与冲击, 2018, 37（06）: 117-123.
LÜ Yuanzheng, XIA Guodong, CHEN Yongchang. Heat transfer characteristics of the micro-jet array impingement driven by rectangular pulses[J]. Journal of Vibration and Shock, 2018, 37（06）: 117-123.
[2] 刘沛清, 高季章, 李永梅. 高坝下游水垫塘内淹没冲击射流实验[J]. 中国科学E辑: 技术科学, 1998, 28(4): 370-377. LIU Peiqing, GAO Jizhang, LI Yongei. Experiments on the submerged jet in a plunge pool[J]. Science in China Series E: Technological Sceinces, 1998, 28(4): 370-377.
[3] CHOO K, FRIEDRICH B K, GLASPELL A W, et al. The influence of nozzle-to-plate spacing on heat transfer and fluid flow of submerged jet impingement[J]. International Journal of Heat and Mass Transfer, 2016, 97: 66-69.
[4] BELTAOS S, RAJARATNAM N. Impingement of axisymmetric developing jets[J]. Journal of Hydraulic Research, 1977, 15（4）: 311-326.
[5] GIRALT F, CHIA C J, TRASS O. Characterization of the impingement region in an axisymmetric turbulent jet[J]. Industrial & Engineering Chemistry Fundamentals, 1977, 16（1）: 21-28.
[6] ALEKSEENKO S V, BILSKY A V, DULIN V M, et al. Experimental study of an impinging jet with different swirl rates[J]. International Journal of Heat and Fluid Flow, 2007, 28（6）: 1340-1359.
[7] PAO Y H. Structure of turbulent velocity and scalar fields at large wavenumbers[J]. Physics of Fluids, 1965, 8（6）: 1063-1075.
[8] NISHINO K, SAMADA M, KASUYA K, et al. Turbulence statistics in the stagnation region of an axisymmetric impinging jet flow[J]. International Journal of Heat and Fluid Flow, 1996, 17（3）: 193-201.
[9] BAYDAR E, OZMEN Y. An experimental investigation on flow structures of confined and unconfined impinging air jets[J]. Heat and mass transfer, 2006, 42（4）: 338-346.
[10] SHEKHAR C, NISHINO K. Turbulence energetics in an axisymmetric impinging jet flow[J]. Physics of Fluids, 2019, 31（5）: 055111.
[11] SATAKE S, KUNUGI T. Direct numerical simulation of an impinging jet into parallel disks[J]. International Journal of Numerical Methods for Heat & Fluid Flow, 1998, 8（7）:768-780.
[12] HADŽIABDIĆ M. LES, RANS and combined simulation of impinging flows and heat transfer[D]. Sarajevo: University of Sarajevo, 2006.
[13] UDDIN N. Turbulence modeling of complex flows in CFD[D]. Germany: University of Stuttgart, 2008.
[14] LEE J L S J. Stagnation region heat transfer of a turbulent axisymmetric jet impingement[J]. Experimental Heat Transfer, 1999, 12(2): 137-156.
[15] HAMMAD K J, MILANOVIC I. Effect of Reynolds number on the turbulent flow structure in the near-wall region of an impinging round jet[C]// 9th Symposium on Fundamental Issues and Perspectives in Fluid Mechanics. Hamamatsu：SFIPFM, 2011.
[16] LAI C C K, SOCOLOFSKY S A. Budgets of turbulent kinetic energy, Reynolds stresses, and dissipation in a turbulent round jet discharged into a stagnant ambient[J]. Environmental Fluid Mechanics, 2019, 19（2）: 349-377.
[17] 陈明, 黄海津, 王多银, 等. 半封闭圆管冲击射流流动特性PIV试验研究[J]. 振动与冲击, 2021, 40（15）: 90-97.
CHEN Ming, HUANG Haijin, WANG Duoyin, et al. PIV tests for flow characteristics of impinging jet in a semi-closed circular pipe[J]. Journal of Vibration and Shock, 2021, 40（15）: 90-97.
[18] WANG X K, NIU G P, YUAN S Q, et al. Experimental investigation on the mean flow field and impact force of a semi-confined round impinging jet[J]. Fluid Dynamics Research, 2015, 47（2）: 025501.
[19] 陈启刚. 基于高频PIV的明渠紊流涡结构研究[D]. 北京: 清华大学, 2014.
[20] KÄHLER C J, ASTARITA T, VLACHOS P P, et al. Main results of the 4th international PIV challenge[J]. Experiments in Fluids, 2016, 57（6）: 97.
[21] DUAN Y C, ZHANG P, ZHONG Q, et al. Characteristics of wall-attached motions in open channel flows[J]. Physics of Fluids, 2020, 32（5）: 055110.
[22] 张星星, 陈明, 许光祥, 等. 有限空间中三维壁面紊动射流流动特性试验研究[J]. 水科学进展, 2019, 30（1）: 93-101.
ZHANG Xingxing, CHEN Ming, XU Guangxiang, et al. An experimental study on the flow characteristics of a three-dimensional turbulent wall jet in a limited space[J]. Advances in Water Science, 2019, 30（1）: 93-101.
[23] RAFFEL M, WILLERT C, SCARANO F, et al. Particle image velocimetry a practical guide[M]. New York:Springer, 2018.
[24] 张兆顺, 崔桂香, 许春晓, 等. 紊流理论与模拟:第二版[M]. 北京: 清华大学出版社, 2017.
[25] HUSSEIN H J, CAPP S P, GEORGE W K. Velocity measurements in a high-Reynolds-number, momentum-conserving, axisymmetric, turbulent jet[J]. Journal of Fluid Mechanics, 1994, 258: 31-75.
[26] DARISSE A, LEMAY J, BENAÏSSA A. Budgets of turbulent kinetic energy, Reynolds stresses, variance of temperature fluctuations and turbulent heat fluxes in a round jet[J]. Journal of Fluid Mechanics, 2015, 774: 95-142.
[27] CRAFT T J, GRAHAM L J W, LAUNDER B E. Impinging jet studies for turbulence model assessment—II. An examination of the performance of four turbulence models[J]. International Journal of Heat and Mass Transfer, 1993, 36(10): 2685-2697.
[28] LUMLEY J L. Computational modeling of turbulent flows[M]//Advances in Applied Mechanics. Amsterdam :Elsevier, 1979.
[29] YADAV H, AGRAWAL A. Self-similar behavior of turbulent impinging jet based upon outer scaling and dynamics of secondary peak in heat transfer[J]. International Journal of Heat and Fluid Flow, 2018, 72: 123-142.
[30] SHEKHAR C, NISHINO K. Turbulence characteristics of radially-confined impinging jet flows[J]. International Journal of Heat and Fluid Flow, 2019, 75: 278-299. |
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