Investigating the distance of the injection jets to the target plate and their number and the use of twisted tape in the rotating jet at various angles and its effect on the average Nusselt number and heat transfer

Document Type : Research Paper

Authors

Department of Mechanical Engineering, Central Tehran Branch, Islamic Azad University, Tehran, Iran

Abstract

There are various industries, each of which is somehow involved in the issue of heat transfer, and in many cases, the goal is to increase the rate of heat transfer. In this study, one, two or four injection jets were used together for cooling and the results were compared in terms of the average Nusselt number. Then, by placing the twisted tape at different angles of 180°, 360° and 720° in the injection jet, the average Nusselt number and the minimum and maximum temperature were checked. The results showed that the diameter of the fluid outflow from the nozzle increases by moving away from the jet opening and approaching the hot plate due to the pressure distribution, and when two jets are used in close proximity, the exit from each vortex is created in this place. When using four jets, the outflow from the jet hits the hot plate and creates vortices. With the increase in the number of jets, the Nusselt number and the maximum temperature on the hot surface also increase. The results showed that the average Nusselt number with the angle of the twisted tape, which is placed inside the rotating jet tube, increases at an angle of 180 degrees and decreases at angles of 270 and 360 degrees. In all cases, using twisted strips, the maximum temperature as well as the minimum temperature of the hot surface are higher than when the non-rotating jet is injected on the hot plate. As the distance of the jet from the plane increases, the Nusselt number decreases.

Keywords

[1] J. Barrau, S. Riera, E. Leveille, L. G. Frechette and J. I. Rosell, Nozzle to plate optimization of the jet impingement inlet of a tailored-width microchannel heat exchanger, Experiment. Thermal Fluid Sci.67 (2015), 81–87.
[2] R. Fernandez-Feria, E. Sanmiguel-Rojas and E.S. Benilov, On the origin and structure of a stationary circular hydraulic jump, Phys. Fluids 31 (2019), no. 7, 072104.
[3] R.J. Goldstein and M.E. Franchett, Heat transfer from a flat surface to an oblique impinging jet, J. Heat Transfer 110 (1988), no. 1, 84–90.
[4] A. Ianiro and G. Cardone, Heat transfer rate and uniformity in multichannel swirling impinging jets, Appl. Thermal Engin. 49 (2012), 89–98.
[5] K. Jambunathan, E. Lai, M. Moss and B.L. Button, A review of heat transfer data for single circular jet impingement, Int. J. Heat Fluid Flow 13 (1999), no. 2, 106–115.
[6] M.F. Koseoglu and S. Baskaya, The role of jet inlet geometry in impinging jet heat transfer, modeling and experiments, Int. J. Thermal Sci. 49 (2010), no. 8, 1417-1426.
[7] A.M. Kuraan, S.I. Moldovan and K. Choo, Heat transfer and hydrodynamics of free water jet impingement at low nozzle-to-plate spacings, Int. J. Heat Mass Transfer 108 (2017), 2211–2216.
[8] M.D. Le, C.M. Hsu, N. Kholili and S.H. Lu, Effects of axial jet-to-wall distance on flow behavior and heat transfer of a wall jet at low Reynolds number, IEEE Int. Conf. Adv. Manufact. (ICAM), 2018, pp. 73–76.
[9] D.H. Lee, J. Song and M. C. Jo, The effects of nozzle diameter on impinging jet heat transfer and fluid flow, J. Heat Transfer 126 (2004), no. 4, 554–557.
[10] O. Manca, P. Mesolella, S. Nardini and D. Ricci, Numerical study of a confined slot impinging jet with nanofluids, Nanoscale Res. Lett. 6 (2011), no. 1, 1–16.
[11] H. Martin, Heat and mass transfer between impinging gas jets and solid surfaces, Adv. Heat Transfer 13 (1977), 1–60.
[12] M. Molana and S. Banooni, Investigation of heat transfer processes involved liquid impingement jets: a review, Brazil. J. Chem. Engin. 30 (2013), 413–435.
[13] L. Nakharintr, P. Naphon and S. Wiriyasart, Effect of jet-plate spacing to jet diameter ratios on nanofluids heat transfer in a mini-channel heat sink, Int. J. Heat Mass Transfer 116 (2018), 352–361.
[14] K. Nanan, K. Wongcharee, C. Nuntadusit and S. Eiamsa-Ard, Forced convective heat transfer by swirling impinging jets issuing from nozzles equipped with twisted tapes, Int. Commun. Heat Mass Transfer 39 (2012), no. 6, 844–852.
[15] P. Naphon, L. Nakharintr and S. Wiriyasart, Continuous nanofluids jet impingement heat transfer and flow in a micro-channel heat sink, Int. J. Heat Mass Transfer 126 (2018), 924–932.
[16] H. Samma, A. Khosrojerdi, M. Rostam-Abadi, M. Mehraein, and Y. Catano-Lopera, Numerical simulation of scour and flow field over movable bed induced by a submerged wall jet, J. Hydroinform. 22 (2020), no. 2, 385–401.
[17] B. Weigand and S. Spring, Multiple jet impingement, TURBINE-09. Proc. Int. Symp. Heat Transfer in Gas Turbine Syst., Begel House Inc., 2009.
[18] P. Xu, B. Yu, S. Qiu, H. J. Poh and A.S. Mujumdar, Turbulent impinging jet heat transfer enhancement due to intermittent pulsation, Int J Thermal Sci 49 (2010), no. 7, 1247–1252.
[19] Y.T. Yang and F.H. Lai, Numerical study of heat transfer enhancement with the use of nanofluids in radial flow cooling system, Int Jo Heat Mass Transfer 53 (2010), no. 25-26, 5895–5904.
Volume 15, Issue 5
May 2024
Pages 297-310
  • Receive Date: 22 October 2022
  • Revise Date: 21 November 2022
  • Accept Date: 02 December 2022