Experimental Comparison of Injection Characteristics of Elliptical and Circular Liquid Jets into an Air Crossflow

Document Type : Research Article

Authors

Department of Aerospace Engineering, Amirkabir University of Technology, Tehran, Iran

Abstract

The flow characteristics of liquid jets issuing from elliptical and circular injectors into an air crossflow were experimentally investigated. Two elliptical injectors with different aspect ratios and a circular injector as the reference case with the same cross-sectional area were employed. The major axis of the elliptical nozzles was aligned parallel and perpendicular to the air crossflow direction. The liquid jet was visualized using shadowgraph technique and a high speed camera was used to record the instantaneous status of the jets. The results revealed that some characteristics of injected liquid jets into the air crossflow such as penetration depth and the trajectory of liquid jet were affected by changing the nozzle exit shape. Based on the obtained results elliptical liquid jets because of the lower stability than circular jet, break up sooner and penetrate lower into the air crossflow. As the normalized breakup height of circular jet is obtained 29.5 but the normalized breakup height of elliptic jet with the aspect ratio of 3 and when its major axis was perpendicular to the crossflow direction, is obtained 21.53. In this study two different breakup regimes were observed, column breakup and bag breakup regimes.

Keywords

Main Subjects


[1] N. Ashgriz, Handbook of atomization and sprays:theory and applications, Springer Science & Business Media, 2011.
[2] M. Broumand, M. Birouk, Liquid jet in a subsonic gaseous crossflow: Recent progress and remaining challenges, Progress in Energy and Combustion Sci- ence, 57 (2016) 1-29.
[3] J. Song, K. Ahn, M.-k. Kim, Y. Yoon, Effects of ori- fice internal flow on liquid jets in subsonic crossflows, Journal of Propulsion and Power, 27(3) (2011) 608- 619.
[4]Y. Song, D. Hwang, K. Ahn, Effect of orifice geometry on spray characteristics of liquid jet in cross flow, in: 55th AIAA Aerospace Sciences Meeting, 2017, pp. 1961.
[5]S. Tambe, S.-M. Jeng, H. Mongia, G. Hsiao, Liquid jets in subsonic crossflow, in: 43rd AIAA Aerospace Sciences Meeting and Exhibit, 2005, pp. 731.
[6] J.A. Schetz, A. Padhye, Penetration and breakup of liquids in subsonic airstreams, AIAA Journal, 15(10) (1977) 1385-1390.
[7] T. Chen, C. Smith, D. Schommer, A. Nejad, Multi- zone behavior of transverse liquid jet in high-speed flow, in: 31st Aerospace Sciences Meeting, 1993, pp.453.
[8] P.-K. Wu, K.A. Kirkendall, R.P. Fuller, A.S. Nejad, Breakup processes of liquid jets in subsonic cross- flows, Journal of Propulsion and Power, 13(1) (1997) 64-73.
[9] C. Iyogun, M. Birouk, N. Popplewell, Trajectory of water jet exposed to low subsonic cross-flow, Atomi- zation and Sprays, 16(8) (2006).
[10] M. Birouk, T. Stäbler, B. Azzopardi, An experimental study of liquid jets interacting with cross airflows, Par- ticle Systems Characterization, 20(1) (2003) 39-46.
[11] J.N. Stenzler, J.G. Lee, D.A. Santavicca, W. Lee, Penetration of liquid jets in a cross-flow, Atomization and Sprays, 16(8) (2006).
[12] E. Gutmark, F. Grinstein, Flow control with noncir- cular jets, Annual review of fluid mechanics, 31(1) (1999) 239-272.
[13] F. Wang, T. Fang, Liquid jet breakup for non-circular orifices under low pressures, International Journal of Multiphase Flow, 72 (2015) 248-262.
[14] E. Farvardin, A. Dolatabadi, Breakup Simulation of Elliptical Liquid Jet in Gaseous Crossflow, in: 42nd AIAA Fluid Dynamics Conference and Exhibit, 2012, pp. 2817.
[15] G. Amini, A. Dolatabadi, Axis-switching and break- up of low-speed elliptic liquid jets, International Jour- nal of Multiphase Flow, 42 (2012) 96-103.
[16] A. Jaberi, M. Tadjfar, A. Sheidani, Experimental Comparison of Breakup and  Flow  Characteristics  of Rectangular and Elliptical Water Jets, Amirkabir Journal of Mechanical Engineering, 51(6) (2018) 31- 40.
[17] H.J. Yoon, J.G. Hong, C.-W. Lee, Correlations for penetration height of single and double liquid jets in cross flow under high-temperature conditions, Atomi- zation and Sprays, 21(8) (2011).
[18] Y. Zheng, Characterization of the initial spray from a jet in crossflow, 2009.
[19] X.-h. Wang, Y. Huang, S.-l. Wang, Z.-l. Liu, Bag breakup of turbulent liquid jets in crossflows, AIAA journal, 50(6) (2012) 1360-1366.