Experimental Studies on the Effects of Nozzle Structures on Characteristics of Submerged Gas Jet Noise

Article Preview

Abstract:

The structures of nozzle outlet have great effects on jet noise generated by submerged gas jet. Five nozzles with different cross-sections were designed to study the influences of nozzle structures on sound levels by experimental methods. The flow characteristics and sound pressure levels were measured and the gas-liquid flows formed by submerged gas jets under different Weber numbers were also observed. The results show that the gas-liquid flows transformed from bubbling regime to jetting regime with the increase of Weber numbers. With respect to bubbling flow, no significant differences in sound levels for different nozzles were found. However, a remarkable increase of acoustic emission was caused by the transformation of flow patterns over the frequency bands of 0.6-4 kHz for all nozzles. In addition, sound pressure levels for elliptical nozzle were much lower than those of other nozzles over the frequency bands of 0.6-4 kHz. Therefore, it would be a reasonable strategy to adopt several elliptical orifices instead of round nozzle to reduce the gas jet noise in the design of underwater exhaust muffler.

You might also be interested in these eBooks

Info:

Periodical:

Pages:

4620-4623

Citation:

Online since:

October 2012

Export:

Price:

Permissions CCC:

Permissions PLS:

Сopyright:

© 2012 Trans Tech Publications Ltd. All Rights Reserved

Share:

Citation:

[1] J. J. Gavigan, E. E. Watson, W. F. King III, Noise generation by gas jets in a turbulent wake, J. Acoust. Soc. Am. Vol. 56 (1974), p.1094.

DOI: 10.1121/1.381039

Google Scholar

[2] A. Vazquez, R. Manasseh, R. M. Sanchez, and G. Metcalfe, Experimental comparison between acoustic and pressure signals from a bubbling flow, Chemical Engineering Science. Vol. 63 (2008), p.5860.

DOI: 10.1016/j.ces.2008.08.032

Google Scholar

[3] L. Chen, R. Manasseh, A. Nikolovska and C. Norwood, Noise generation by an underwater gas jet, Proc. 8th Western Pacific Acoustics Conference, Melbourne, Australia, 7-9 April, (2003).

Google Scholar

[4] V. K. Arghode1, A. K. Gupta and K. H. Yu, Effect of nozzle exit geometry on submerged jet characteristics in underwater propulsion, Proc. 46th AIAA Aerospace Sciences Meeting and Exhibit, Reno, Nevada, 7-10 January (2008).

DOI: 10.2514/6.2008-1158

Google Scholar