setsci

Setsci conference indexing system

2618-6446

SET Technology

3386d4e9-cad5-4d2e-afe7-4ac6fa51b20d

Thermal Characteristics of Swirling Coaxial Confined Impinging Air Jets: An Experimental Investigation

Markal

Burak

Recep Tayyip Erdogan University

31 12 2018

3 66 71

2018

SET Technology

CC BY 4.0

The present study investigates the heat transfer characteristics of swirling coaxial confined impinging turbulent air jets. Experimental range covers different values of dimensionless nozzle-to-plate distance (H / D = 0.5, 1 and 2) and dimensionless flowrate ratio (Q* = 0.2 and 0.5). The total flowrate is kept constant at 1.16 x 10-3 m3 s-1 (70 L/min) during the tests. The results are also compared to those obtained for the conventional single circular jets (Q* = 0). It is concluded that both the intensity and the radial uniformity of the heat transfer are improved by increasing dimensionless flowrate ratio. On the other hand, increasing nozzle-to-plate distance causes a decrement in the magnitude of Nusselt numbers.

Impingement, swirling jet, coaxial, heat transfer, radial uniformity

D. W. Colucci, and R. Viskanta, “Effect of nozzle geometry on local convective heat transfer to a confined impinging air jet,” Exp. Therm Fluid Sci., vol. 13, pp. 71−80, 1996.

X. Gao, and B. Sunden, “Experimental investigation of the heat transfer characteristics of confined impinging slot jets,” Exp. Heat Transf., 16, pp. 1–18, 2003.

M. F. Koseoglu, and S. Baskaya, “The effect of flow field and turbulence on heat transfer characteristics of confined circular and elliptic impinging jets,” Int. J. Therm Sci., vol. 47, pp. 1332–1346, 2008.

S. Eiamsa-ard, K. Nanan, and K. Wongcharee, “Heat transfer visualization of co/counter-dual swirling impinging jets by thermochromic liquid crystal method,” Int. J. Heat Mass Transf., vol. 86, pp. 600–621, 2015.

H. Maki, and A. Yabe, “Heat transfer by the annular impinging jet, Exp. Heat Transf., vol. 2:1, pp. 1−12, 1989.

L. Huang, and M. S. EL-Genk, “Heat transfer and flow visualization experiments of swirling, multi-channel, and conventional impinging jets,” Int. J. Heat Mass Transf., vol. 41, pp. 583–600, 1998.

M. Can, and A. B. Etemoglu, “Investigation into methods of enhancing heat transfer under impinging air jets,” Exp. Heat Transf., vol. 16:3, pp. 171−190, 2003.

C. Nuntadusit, M. Wae-hayee, A. Bunyajitradulya, and S. Eiamsa-ard, “Visualization of flow and heat transfer characteristics for swirling impinging jet,” Int. Commun. Heat Mass Transf., vol. 39, pp. 640– 648, 2012.

M. Wae-Hayee, P. Tekasakul, S. Eiamsa-ard, and C. Nuntadusit, “Flow and heat transfer characteristics of in-line impinging jets with cross-flow at short jet-to-plate distance, Exp. Heat Transf., vol. 28:6, pp. 511−530, 2015.

Z. U. Ahmed, Y. M. Al-Abdeli, and F. G. Guzzomi, “Heat transfer characteristics of swirling and non-swirling impinging turbulent jets,” Int. J. Heat Mass Transf., vol. 102, pp. 991–1003, 2016.

Z. U. Ahmed, Y. M. Al-Abdeli, and F. G. Guzzomi, “Flow field and thermal behaviour in swirling and non-swirling turbulent impinging jets,” Int. J. Therm. Sci., vol. 114, pp. 241–256, 2017.

B. Markal, “Experimental investigation of heat transfer characteristics and wall pressure distribution of swirling coaxial confined impinging air jets,” Int. J. Heat Mass Transf., vol. 124, pp. 517–532, 2018.

B. Markal, and O. Aydin, “Experimental investigation of coaxial impinging air jets,” Appl. Therm. Eng., vol. 141, pp. 1120–1130, 2018.

S. J. Kline, and F. A. McClintock, “Describing uncertainties in single sample experiments,” Mech. Eng., vol. 75 (1), pp. 3–8, 1953.

Y. Ozmen, “Confined impinging twin air jets at high Reynolds numbers,” Exp. Therm Fluid Sci., vol. 35, pp. 355–363, 2011.