Dominant Flow Features of Two Inclined Impinging Jets Confined in Large Enclosure

Authors: T. Chammem, H. Mhiri, O. Vauquelin

Abstract:

The present study was provided to examine the vortical structures generated by two inclined impinging jets with experimental and numerical investigations. The jets are issuing with a pitch angle α=40° into a confined quiescent fluid. The experimental investigation on flow patterns was visualized by using olive particles injected into the jets illuminated by Nd:Yag laser light to reveal the finer details of the confined jets interaction. It was observed that two counter-rotating vortex pairs (CVPs) were generated in the near region. A numerical investigation was also performed. First, the numerical results were validates against the experimental results and then the numerical model was used to study the effect of section ratio on the evolution of the CVPs. Our results show promising agreement with experimental data, and indicate that our model has the potential to produce useful and accurate data regarding the evolution of CVPs.

Keywords: Inclined impinging jets, counter-rotating vortex pair, CFD, experimental investigation, section ratio.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1077225

References:

[1] R.J. Margason, "Fifty years of jet in cross flow research. In Computational and Experimental Assessment of Jets in Cross Flow. Proceedings of NATO AGARD Conference, CP-534, Winchester, UK. 1993.
[2] T.F. Fric, A. Roshko, "Vortical structure in the wake of a transverse jet," Journal of Fluid Mechanics, vol. 279, pp. 1-47, 1993.
[3] L. L.Yuan, R. L. Street, & J. H. Ferziger, "Large-eddy simulations of a round jet in crossflow," J. Fluid Mech. Vol. 379, pp.71-104, 1999.
[4] B.R. Morton, A. Ibbetson, "Jets deflected in a crossflow," Experimental Thermal and Fluid Science, vol. 12, pp.112-133, 1996.
[5] J. F. Keffer and W. D. Bains, "The Round turbulent jet in a cross-wind," J. Fluid Mech. Vol. 15, pp. 481-496, 1963.
[6] K.B. Mc Grattan. H.R. Baum and R.G. Rehm," Numerical simulation of smoke plumes from large oil fires," Atmospheric Environment, vol. 30, pp. 4125-4136, 1996.
[7] R. Fearn, and R.P. Weston, "Vorticity associated with a jet in a crossflow," AIAA J. vol. 12, pp. 1671-1975, 1666.
[8] M. Gregoric, L.R. Davis, D.J. Bushnell, "An experimental investigation of merging buoyant jets in a crossflow." ASME J. Heat Transfer, vol. 104, pp. 236-240, 1982.
[9] A.R. Karagozian, T.T. Nguyen, C.N. Kim, "Vortex modeling of single and multiple dilution jet mixing in a cross flow," J. Propul. Power 2, 354-360, 1986. RS=12 RS=21 RS=48 RS=133
[10] J.M.M. Barata, D.F.G. Durao, M.V. Heitor, J.J. McGuirk, "Impingement of single and twin turbulent jets through a crossflow," AIAA J. vol.29, pp.595-602, 1991.
[11] V. Kolar, H. Takao, T. Todoroki, E. Savory, S. Okamoto, N. Toy, "Vorticity transport within twin jets in crossflow," Exp. Therm. Fluid Sci. vol.27, pp.563-571, 2003.
[12] V. Kolar, E. Savory, H. Takao, T. Todoroki, S. Okamoto, N. Toy, "Vorticity and circulation aspects of twin jets in crossflow for an oblique nozzle arrangement," IMechE J. Aerospace Eng. Vol.220, pp.247-252, 2006.
[13] V.Kolar, E. Savory, "Dominant flow features of twin jets and plumes in crossflow," Journal of Wind Engineering and Industrial Aerodynamics vol."95, pp.1199-1215, 2007.
[14] R.L.J.Fernandes., A. Sobiesiak., A. Pollard., opposit round jets issuing into a small aspect ratio channel cross flow," Experimental Thermal and Fluid Science. Vol.13, pp.374-394, 1996.
[15] M. S. Perchanok, D. M. Bruce, I. S. Gartshore, "Velocity measurements in an isothermal scale model of a hog fuel boiler furnace," J, Pulp Paper Sci. vol.15, pp.212-219, 1989.
[16] K. S. Chen, J,Y. Hwang, "Experimental study on the mixing of one and Dual-Line heated jets with a cold crossflow in a confined channel," AIAA J, vol.29, pp.353-360, 1991.
[17] Kazuyoshi Nakabe, Elzbieta Fornalik, Jens F. Eschenbacher et al., "Ineractions of longitudinal vortices generated by twin inclined jets and enhancement of impingement heat transfer," International Journal of heat and fluid flow,vol.22, pp.287-292, 2001.
[18] EH. Mathews, "Numerical solutions of fluid problems related to buildings, structures and the environment," Building and Environment, 24 (1):1. 1989.
[19] BE. Launder, DB. Spalding, "The numerical computation of turbulent flows," Computer Methods in Applied Mechanics and Engineering, vol.3, pp.269-89, 1974.
[20] S. Murakami, "Prediction, analysis and design for indoor climate in large enclosures," Roomvent -92. In: Proceedings of third international conference. DANVAK, 1992.
[21] Q. Chen, Z. Jiang, "Significant questions in predicting room air motion," ASHRAE Transactions, vol.98(1), pp.929-38, 1992.
[22] PG. Schild, PO. Tjelflaat, D. Aiulfi, "Guidelines for CFD modeling of atria," ASHRAE Transaction, vol.101(2), pp.1311-29, 1995.
[23] B.Kader, Temperature and concentration profiles in fully turbulent boundary layers," Int. J.Heat Mass Transfer vol.24, pp.1541-1544, 1993.
[24] M. Wolfstein, "The Velocity and Temperature Distribution of One- Dimensional Flow with Turbulence Augmentation and Pressure Gradient," Int. J. Heat Mass Transfer, vol.12, pp.301-318, 1969.