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Direct evaluation of aeroacoustic theory in a jet

Published online by Cambridge University Press:  26 April 2006

James Bridges  and
Fazle Hussain
James Bridges
Affiliation:
Department of Mechanical Engineering, University of Houston, Houston. TX 77204-4792, USA Present address: Sverdrup Technology, Inc., NASA Lewis Group, 2001 Aerospace Parkway, Brook Park, OH 44142, USA.
Fazle Hussain
Affiliation:
Department of Mechanical Engineering, University of Houston, Houston. TX 77204-4792, USA
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Abstract

This paper provides a unique, detailed evaluation of basic aeroacoustic theory applied to low-Mach-number (M = 0.08) cold jets. In contrast to most prior studies comparing theoretical predictions of jet noise with experimental results, our comparison uses a relatively complete knowledge of the flow field and employs vortex sound theory — an acoustic analogy which is shown to be insensitive to those aspects of the flow field about which our knowledge is incomplete. The primary result is that the measured sound field directivity of vortex ring pairing in circular jets is very similar to that predicted by theory: a stationary, axisymmetric, lateral quadrupole. This directivity is very unlike the monotonic polar dependence found in time-average measures of jet noise fields and unlike the directivity found in similar excited jet experiments. Although not perfect, the agreement between experiment and theory here is satisfyingly close in comparison to the discrepancies found by Huerre & Oighton (1983). Our result also proves that pairing of purely axisymmetric coherent structures is not the dominant sound source in low-Mach-number jets and that vortex asymmetry must be an essential aspect of the vortex motions which produce noise in such jets.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 240 , July 1992 , pp. 469 - 501
Copyright
© 1992 Cambridge University Press

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References

Ahuja, K. K. 1973 J. Sound. Vib. 29, 155.
Bendat, J. S. & Piersal, A. G. 1980 Engineering Applications of Correlation and Spectral Analysis. Wiley.
Bridges, J. E. 1990 Application of coherent structure and vortex sound theories to jet noise: Ph.D. Thesis, University of Houston.
Bridges, J. E. & Hussain, A. K. M. F. 1987 J. Sound Vib. 117, 289.
Broadbent, E. G. & Moore, D. W. 1979 Phil. Trans. R. Soc. Lond. A290, 353.
Crighton, D. G. 1972 J. Fluid Mech. 56, 683.
Crighton, D. G. & Huerre, P. 1990 J. Fluid Mech. 220, 355.
Crow, S. C. 1970 Stud. App. Maths 46, 21.
Curle, N. 1955 Proc. R. Soc. Lond. A231, 505.
Ffowcs Williams, J. E. & Hall, L. H. 1970 J. Fluid Mech. 40, 657.
Glegg, S. A. L. 1982 J. Sound Vib. 80, 31.
Goldstein, M. E. 1976 Aeroacoustics. McGraw-Hill.
Hasan, M. A. Z. & Hussain, A. K. M. F. 1985 J. Fluid Mech. 150, 159.
Howe, M. S. 1975 J. Fluid Mech. 71, 625.
Huerre, P. & Crighton, D. G. 1983 AIAA 8th Aeroacoustics Cong. AAIA-83–0661 (referred to herein as HC).
Hussain, A. K. M. F. 1983 Phys. Fluids 26, 2816.
Kambe, T. 1984 J. Sound Vib. 95, 351.
Kambe, T. 1986 J. Fluid Mech. 173, 643.
Kambe, T. & Minota, T. 1981 J. Sound Vib. 74, 61.
Kempton, A. J. 1976 J. Sound Vib. 48, 475.
Laufer, J. & Monkewitz, P. 1980 AIAA 6th Aeroacoustics Conf. AAIA-83–0661.
Laufer, J. & Yen, T.-C. 1983 J. Fluid Mech. 134, 1 (referred to herein as LY).
Lighthill, M. J. 1952 Proc. R. Soc. Lond. A211, 564.
Lush, P. A. 1971 J. Fluid Mech. 46, 477.
Möhring, W. 1978 J. Fluid Mech. 85, 685.
Möhring, W. 1990 J. Sound Vib. 140, 155.
Moore, C. J. 1977 J. Fluid Mech. 80, 321.
Obermeier, F. 1985 J. Sound Vib. 99, 111.
Powell, A. 1964 J. Acoust. Soc. Am. 36, 177.
Richarz, W. G. 1980 J. Acoust. Soc. Am. 67, 73.
Zaman, K. B. M. Q. & Hussain, A. K. M. F. 1978 J. Fluid Mech. 87, 349.
Zaman, K. B. M. Q. & Hussain, A. K. M. F. 1980 J. Fluid Mech. 101, 449.