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A Study on the Aerodynamic Noise of a Supersonic Exhaust Nozzle of Slotted Tube
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 Title & Authors
A Study on the Aerodynamic Noise of a Supersonic Exhaust Nozzle of Slotted Tube
Lee, Dong-Hoon; Seto, Kunisato;
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 Abstract
The objective of this study is to experimentally investigate the noise propagating characteristics, the noise reduction mechanism and the performance of a slotted tube attached at the exit plane of a circular convergent nozzle. The experiment is performed through the systematic change of the jet pressure ratio and the slot length under the condition of two kinds of open area ratios, 25% and 51%. The open area ratio calculated by the tube length equivalent for the slot length is defined as the ratio of the total slot area to the surface area of a slotted tube. The experimental results for the near and far field sound, the visualization of jet structures and the static pressure distributions in the jet passing through a slotted tube are presented and explained in comparison with those for a simple tube. The propagating characteristics of supersonic jet noises from the slotted tube is closely connected with the slot length rather than the open area ratio, and its propagating pattern is similar to the simple tube. It is shown that the slotted tube has a good performance to suppress the shock-associated noise as well as the turbulent mixing noise in the range of a limited jet pressure and slot dimension. The considerable suppression of the shock‘associated noise is mainly due to the pressure relief caused by the high-speed jets passing through the slots on the tube. Both the strength of shock waves and the interval between them in a jet plume are decreased by the pressure relief. Moreover, the pressure relief is divided into the gradual and the sudden relief depending upon the open area ratio of the slotted tube. Consequently, the shock waves in a jet plume are also changed by the type of pressure relief. The gradual pressure relief caused by the slotted tube with the open area ratio 25% generates the weak oblique shock waves. On the contrary, the weak normal shock waves appear due to the sudden pressure relief caused by the slotted tube with the open area ratio 51%.
 Keywords
Aerodynamic Noise;Turbulent Mixing Noise;Shock-Associated Noise;Shock Wave;Slotted Tube;
 Language
Korean
 Cited by
 References
1.
Powell, A., 1953, 'On the Mechanism of Choked Jet Noise', Proceedings of the Physical Society, 66, pp. 1039-1056 crossref(new window)

2.
Harper-Bourne, M. and Fisher, M.J., 1973, 'The Noise from Shock Waves in Supersonic Jets,' Proceedings (No. 131) of the AGARD Conference on Noise Mechanisms, Brussels, Belgium, pp. 11-1-11-13

3.
Dosanjh, D.S., Yu, J.C. and Abdelhamid, A.N., 1971, 'Reduction of Noise from Supersonic Jet Flows,' AlAA Joumal, Vol. 9, No. 12, pp.2346-2353

4.
Wlezien, R.W. and Kibens, V., 1988, 'Influence of Nozzle Asymmetry on Supersonic Jets,' AIAA Journal, Vol. 26, No.1, pp. 27-33

5.
Seto, K., 1988, 'Modification of the Characteristics of Underexpanded Jets by Using an Extended Perforated Tube as a Noise Suppressor,' Noise Control Engineering Journal, Vol. 30, No. 3, pp. 119-125

6.
Samimy, M., Zaman, K.B.M.Q. and Reeder, M.F., 1993, 'Effects of Tabs on the Flow and Noise Field of an Axisymmetric Jet,' AIAA Journal, Vol. 31, No. 4, pp. 609-619

7.
Meier, G.E.A., Selerowicz, W.C. and Szumowski, A.P., 1990, 'A Nozzle Generating Low Jet Noise,' Jr. of Sound and Vibration, Vol. 136, No.1, pp. 65-73 crossref(new window)

8.
Nagamatsu, H.T., SHEER Jr., R.E. and Gill, M.S., 1972, 'Characteristics of Multitube Multishroud Supersonic Jet Noise Suppressor,' AIAA Journal, Vol. 10, No. 3, pp. 307-313

9.
Fujii, S., Nishiwaki, H. and Takeda, K., 1981, 'Suppression of Jet Noise Peak by Velocity Profile Reshaping,' AIAA Journal, Vol. 19, No. 7, pp. 872-877

10.
Kibens, V. and Wlezien, R.W., 1985, 'Noise Reduction Mechanisms in Supersonic Jets with Porous Centerbodies,' AIAA Journal, Vol. 23, No. 5, pp. 678-684

11.
Norum, T.D., 1983, 'Screech Supression in Supersonic Jets,' AIAA Journal, Vol. 121, No. 2, pp. 235-240

12.
Seto, K., Lee, D.H., Zhi, Xiang XU and Takase, N., 1998, 'A Study on the Mechanism of Noise Reduction of the Slotted Nozzle,' 日本航空宇宙學會, 第29期年會講演會, 講演集 pp. 66-67

13.
Krothapalli, A., McDaniel, J. and Baganoff, D., 1990, 'Effect of Slotting on the Nozzle of an Axisymmetric Supersonic Jet,' AIAA Journal, Vol. 28, No. 12, pp. 2136-2138

14.
Nagel, R.T., Denham, J.W. and Papathanasiou, A.G., 1983, 'Supersonic Jet Screech Tone Cancellation,' AIAA Journal, Vol. 21, No. 11, pp. 1541-1545

15.
Abdel-Fattah, A.M., 1988, 'Discrete Tone Emission from High-Pressure Ratio Supersonic Jets from Convergent-Divergent Nozzles,' AIAA Journal, Vol. 26, No. 3, pp. 283-291