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Parametric Study of the Flow Characteristics and Heat Transfer from Circular Intermittent Jet Impinging on a Concave Surface | ||
| Journal of Heat and Mass Transfer Research | ||
| دوره 8، شماره 2 - شماره پیاپی 16، دی 2021، صفحه 173-186 اصل مقاله (2.09 M) | ||
| نوع مقاله: Full Lenght Research Article | ||
| شناسه دیجیتال (DOI): 10.22075/jhmtr.2021.22009.1319 | ||
| نویسندگان | ||
| Mehran Rajabi Zargarabadi* 1؛ Saeed Rakhsha2؛ Syfolah Saedodin3 | ||
| 1Faculty of Mechanical Engineering | ||
| 2Faculty of Mechanical Engineering, Semnan University, Semnan, Iran | ||
| 3Faculty of Mechanical Engineering, Semnan University, Iran | ||
| تاریخ دریافت: 13 آذر 1399، تاریخ بازنگری: 02 آبان 1400، تاریخ پذیرش: 28 آبان 1400 | ||
| چکیده | ||
| The main purpose of the current work is the analysis of the pulsating effect on the flow and heat transfer from impinging jet on a concave surface. In this way, the heat flux of 2300 W/m2 has been applied constantly on the surface with the radius of 120mm. The intermittent jet has been created for the frequency range of 1-100Hz by the pulsed-jet generator. Nusselt number distribution and flow field have been investigated for dimensionless distance of nozzle to surface (H/d) 2 to 5 and Reynolds number from 7000 to 13000. The comparison of the experimental data with Numerical simulation shows that the k-ε RNG turbulence model is appropriately capable of predicting the Nusselt number on the concave surface under the pulsed jet impinging. Results of the present research indicate that, pulsating the jet is more effective on the concave surface in comparison with a flat surface. Also as compared to steady jet, when pulsating applies to the inlet jet with low frequency, reduction in Nusselt number is acquired. Furthermore, at each Re number and H/d, a threshold Strouhal number is found above which the Nusselt number of the pulsed jet is greater than that of the steady jet. Moreover, for the low nozzle to surface distance, Nu of stagnation point at low and high frequency is varied with Sr=0.05 and Sr=0.15, respectively. At Re=10000, pulsating the impinging jet with f =100Hz causes an increase in the time and area-averaged of Nusselt number by 22% and 20% in comparison to steady jet at H/d=5 and 2, respectively. | ||
| کلیدواژه‌ها | ||
| Impinging jet؛ Nusselt number؛ pulse frequency؛ concave surface | ||
| عنوان مقاله [English] | ||
| مطالعه مشخصه های جریان و انتقال حرارت جت برخوردی دایروی متناوب به سطح مقعر | ||
| چکیده [English] | ||
| هدف مطالعه حاضر، بررسی و تحلیل اثر نوسانی کردن جت ورودی بر روی جریان و انتقال حررات جت برخوردی دایره ای بر سطح مقعر است. به این ترتیب، شار حرارت W/m2 2000 بر روی سطح با شعاع 120 میلی متر اعمال شده است. جت نوسانی برای محدوده فرکانس 1-100 هرتز توسط دستگاه تولید جریان نوسانی ایجاد شده است. توزیع عدد نوسلت و میدان جریان برای فاصله بدون بعد نازل تا سطح مقعر، 2 تا 5 و عدد رینولدز از 7000 تا 13000 بررسی شده است. مقایسه داده‌های تجربی با شبیه‌سازی عددی نشان می-دهد که مدل آشفتگی k-ε RNG به طور مناسب قادر به پیش بینی عدد نوسلت در امتداد سطح مقعر می باشد. نتایج تحقیق حاضر نشان می‌دهد که، جت نوسانی روی سطح مقعر در مقایسه با سطح تخت موثرتر است. همچنین در مقایسه با جت ثابت، نوسانی کردن جت ورودی با فرکانس پایین باعث کاهش Nu می‌شود. علاوه بر این، در هر Re و H / d، یک عدد آستانه استروهال یافت می‌شود که برای مقادیر بیشتر از آن، مقدار عدد Nu جت نوسانی بیشتر از جت ثابت است. نتایج نشان می‌دهد، برای فاصله‌های کم نازل تا سطح برخورد، Nu نقطه سکون در فرکانس های کم و زیاد به ترتیب با Sr0.05 و Sr 0.15 متناسب است. در Re = 10000 ، نوسانی کردن جت ورودی با f = 100Hz در مقایسه با جت ثابت، باعث افزایش متوسط زمانی و مکانی عدد ناسلت به اندازه % 22 و %20 در H/d های 2 و 5 می گردد. | ||
| کلیدواژه‌ها [English] | ||
| جت برخوردی, فرکانس نوسان, عدد استروهال, عدد ناسلت, صفحه مقعر | ||
| مراجع | ||
|
[1] A. Hadipour, M. Rajabi Zargarabadi, M. Dehghan, Effect of micro‑pin characteristics on flow and heat transfer by a circular jet impinging to the flat surface, Journal of Thermal Analysis and Calorimetry, 140, 943–951, (2020).
[2] H. Ramezanzadeh, A. Ramiar, M.Yousefifard, M. Ghasemian, Numerical analysis of sinusoidal and step pulse velocity effects on an impinging jet quenching Process, Journal of Thermal Analysis and Calorimetry, 140,331–349, (2020).
[3] M. Ataei, R. Tarighi, A. Hajimohammadi, M. Rajabi zargarabadi, Heat Transfer under Double Turbulent Pulsating Jets Impinging on a Flat Surface, Journal of Heat and Mass Transfer Research, 4, 45-52,(2017).
[4] R. V. Hout, V. Rinsky, Y. G. Grobman, Experimental study of a round jet impinging on a flat surface: Flow field and vortex characteristics in the wall jet, Int. J. Heat and Fluid Flow, 70, 41-58,(2018).
[5] P. Xu, A. P. Sasmito, S. Qiu , A. S. Mujumdar , L. Xu, L. Geng, Heat transfer and entropy generation in air jet impingement on a model rough surface, International Communications in Heat and Mass Transfer, 72, 48–56, (2016).
[6] H. Ramezanzadeh, A. Ramiar, M. Yousefifard, Numerical analysis of sinusoidal and step pulse velocity effects on an impinging jet quenching process, J Therm Anal Calorim, 140, 331–349 (2020).
[7] M. Haines, I. Taylor, The turbulence modelling of a pulsed impinging jet using LES and a divergence free mass flux corrected turbulent inlet, Journal of Wind Engineering and Industrial Aerodynamics, 188, 338-364, (2019).
[8] P. Xu, S. Qiu, M. Zhou Yu, X. Qiao, A. S. Mujumdar, A study on the heat and mass transfer properties of multiple pulsating impinging jets, International Communications in Heat and Mass Transfer, 39, 378–382, (2012).
[9] T. Ikeda, Y. Mori, Y. Tsuchiya, T. Nagasawa, T. Horikosi, A Study on Pulsating Jet (Observation on the Behavior of the Vortices by Means of Flow Visualization), Journal of the Visualization Society of Japan, 17(67), 292-297, (1997).
[10] D. J. Sailor, , J.R. Daniel, F. Qianli, Effect of Variable Duty Cycle Flow Pulsations on Heat Transfer Enhancement for an Impinging Air Jet, Int. Journal of Heat and Fluid Flow,20, 574-580, (1999).
[11] H. J. Poh, K. Kumar, A.S. Mujumdar, Heat transfer from a pulsed laminar impinging jet, Int. Communications in Heat and Mass Transfer, 32, 1317-1324, (2005).
[12] X. Peng, A. S. Mujumdar, P. H. Joo and Y. Boming, Heat transfer under a pulsed slot turbulent impinging jet at large temperature differences, Thermal science, 14(1), 271-281, (2010).
[13] R.C Bejera, P. Dutta, K.Srinivasan, Numerical Study of Interrupted Impinging Jets for Cooling of Electronics, IEEE Transactions on Components and Packaging Technologies, 30(2), 275-284, (2007).
[14] J.W. Zhou, G. Wang, G. Middelberg, H. Herwig, Unsteady jet impingement: heat transfer on smooth and non-smooth surfaces, Commun Heat Mass Transf, 36,103–110. (2008).
[15] J. C. Kurnia, A. P. Sasmito P. Xu, A. S. Mujumdar, Performance and potential energy saving of thermal dryer with intermittent impinging jet, Applied Thermal Engineering,113, 246-258, (2017).
[16] H.J. Poh, and A.S. Mujumdar, Heat Transfer from a Pulsed Turbulent Impinging Jet at Large Temperature Differences, Proceedings, 5 th Asia-Pacific Drying Conference, Hong Kong, 1171-1177, (2007).
[17] G. Middelberg, and H. Herwig. Convective heat transfer under unsteady impinging jets: the effect of the shape of the unsteadiness, Heat Mass Transfer, 45, 1519–1532, (2009).
[18] R. Zulkifli, K. Sopian, S. Abdullah, and M.S. Takriff, Comparison of local Nusselt number for steady and pulsating circular jet at Reynolds number of 16000, European Journal of Scientific Research, 29, 369-378, (2009).
[19] J. Mohammadpour, M. Zolfagharian, A. S. Mujumdarb, M. Rajabi Zargarabadi, M. Abdula Hzadeh, Heat transfer under composite arrangement of pulsed and steady turbulent submerged multiple jets impinging on a flat surface, International Journal of Thermal Sciences, 86, 139-147, (2014).
[20] S. M. Hosseinalipour, S. Rashidzadeh, M. Moghimi, K. Esmailpour, Numerical study of laminar pulsed impinging jet on the metallic foam blocks using the local thermal non‑equilibrium model, Journal of Thermal Analysis and Calorimetry, (2019).
[21] H. Eren, N. Celik, B. Yesilata, Nonlinear flow and heat transfer dynamics of a slot jet impinging on a slightly curved concave surface, International Communications in Heat and Mass Transfer, 33, 364–371, (2006).
[22] Z. Ying, L.Guiping, B. Xueqin, B. Lizhana, W.D. Shenga, Experimental study of curvature effects on jet impingement heat transfer on concave surfaces, Chinese Journal of Aeronautics, 30, 586-594, (2017).
[23] J. Taghinia, M. Rahman, T. Siikonen, Heat transfer and flow analysis of jet impingement on concave surfaces, Applied Thermal Engineering, 84, 448-459, (2015).
[24] A. Hashiehbaf, A. Baramade, A. Agrawal, G.P. Romano, Experimental investigation on an axisymmetric turbulent jet impinging on a concave surface, International Journal of Heat and Fluid Flow, 53, 167–182, (2015).
[25] J. Mohammadpour, M. Rajabi-Zargarabadi, A. S.Mujumdar, H. Ahmadia, Effect of intermittent and sinusoidal pulsed flows on impingement heat transfer from a concave surface, International Journal of Thermal Sciences, 76, 118-127, (2014).
[26] M. Rajabi, E. Rezaei, B.Yousefi, Numerical analysis of turbulent flow and heat transfer of sinusoidal pulsed jet impinging on an asymmetrical concave surface, Applied Thermal Engineering, 128, 578-585, (2018).
[27] D. Qiu, C. Wang, L. Luo, S. Wang, Z. Zhao, Z. Wang, On heat transfer and flow characteristics of jets impinging onto a concave surface with varying jet arrangements, Journal of Thermal Analysis and Calorimetry, (2019).
[28] S.J. Kline, F.A. McClintock, Describing uncertainties in single sample experiments, Mech. Eng. 75, 3–8, (1953).
[29] N. Kharoua, L. Khezzar, Z. Nemouchi, M. Alshehhi, LES study of the combined effects of groups of vortices generated by a pulsating turbulent plane jet impinging on a semi-cylinder, Applied Thermal Engineering, 114, 948-960, (2017).
[30] C.G. Speziale, S. Thangam, Analysis of an RNG based turbulence model for separated flows, International Journal of Engineering Science, 30, 1379-1388, (1992).
[31] H Ahmadi, M Rajabi-Zargarabadi, A.S. Mujumdar, J Mohammadpour, Numerical modeling of turbulent semi-confined slot jet impinging on a concave surface, Thermal Science, 19(1), 129-140, (2015).
[32] E. Öztekin , O. Aydin , M. Avci, Heat transfer in a turbulent slot jet flow impinging on concave surfaces, International Communications in Heat and Mass Transfer, 44, 77–82, (2013).
[33] S.V. Patankar, Numerical Heat Transfer and Fluid Flow, Hemisphere Publishing, Company. (1980).
[34] M. A. Pakhomov, V. J. Terekhov, Numerical study of fluid flow and heat transfer characteristics in an intermittent turbulent impinging round jet, International Journal of Thermal Sciences, 87, 85-93, (2015).
[35] H.M. Hofmann , D. L. Movileanu , M. Kind, H. Martin Influence of a pulsation on heat transfer and flow structure in submerged impinging jets, International Journal of Heat and Mass Transfer, 50, 3638–3648, (2007).
[36] M. Raizner, V. Rinsky, G. Grossman, R. van Hout, Heat transfer and flow field measurements of a pulsating round jet impinging on a flat heated surface, International Journal of Heat and Fluid Flow, 77, 278–287, (2019).
[37] S. Rakhsha, M. Rajabi Zargarabadi, and S. Saedodin, Experimental and numerical study of flow and heat transfer from a pulsed jet impinging on a pinned surface, EXPERIMENTAL HEAT TRANSFER, (2020).
[38] C. Braud, A. Liberzon, Real-time processing methods to characterize streamwise vortices, Journal of Wind Engineering & Industrial Aerodynamics, 179, 14–25, (2018).
[39] H. Yadav, A. Agrawal, A. Srivastava, Mixing and entrainment characteristics of a pulse jet, International Journal of Heat and Fluid Flow, 61, 1–13, (2016).
[40] S. Ghadi, K. Esmailpour, S.M. Hosseinalipour, A. S. Mujumdar, Experimental study of formation and development of coherent vortical structures in pulsed turbulent impinging jet, Experimental Thermal and Fluid Science,74, 382-389, (2016).
[41] A. Hadipour, M. Rajabi Zargarabadi, Heat transfer and flow characteristics of impinging jet on a concave surface at small nozzle to surface distances, Applied Thermal Engineering, 138, 534-541, (2018).
[42] R.B. Kalifa, S. Habli , N. Mahjoub Saïd ,H. Bournot ,G. L. Pale, Parametric analysis of a round jet impingement on a heated plate, International Journal of Heat and Fluid Flow, 57, 11-23, (2016).
[43] L. A. Brignoni, S. V. Garimella, Effects of nozzle-inlet chamfering on pressure drop and heat transfer in confined air jet impingement, International Journal of Heat and Mass Transfer,43,1133-1139, (2000).
[44] M.A.R. Sharif, K.K. Mothe, Parametric study of turbulent slot-jet impingement heat transfer from concave cylindrical surfaces, International Journal of Thermal Sciences, 49, 428–442, (2010).
[45] C. M. Hsu, W. C. Jhan, Y. Y. Chang, Flow and heat transfer characteristics of a pulsed jet impinging on a flat plate, Heat and Mass Transfer, (2019). | ||
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