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On sound generation by weakly nonlinear interactions of surface gravity waves

Published online by Cambridge University Press:  21 April 2006

Y. P. Guo
Y. P. Guo
Affiliation:
Department of Engineering, University of Cambridge, Trumpington Street, Cambridge CB2 1PZ, UK
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Abstract

The theory of sound generation by weakly nonlinearly interacting ocean surface waves is examined. The main conclusion is that this mechanism may not be a strong generator of ocean sound. It is shown that at low frequency and with small wind the sound generated by this mechanism is weak in comparison with that directly radiated by the turbulent airflow, the flow which is also the cause of surface waves. With increasing frequency and/or wind speed, the sound from surface-wave interactions becomes appreciable, but it is found that the condition for this sound overwhelming the aerial turbulence radiation implies the precise condition at which fully nonlinear surface motions occur. In that case processes such as splashing of water sprays by breaking waves become the main cause of ocean noise. In fact it seems that the weakly nonlinear mechanism proposed by Brekhovskikh is never an important source of sound in the real ocean.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 181 , August 1987 , pp. 311 - 328
Copyright
© 1987 Cambridge University Press

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References

Batchelor, G. K. 1959 The Theory of Homogeneous Turbulence. Cambridge University Press.
Brekhovskikh, L. M. 1966 Underwater sound waves generated by surface waves in the ocean. Izv. Atmos. Oceanic Phys. 2, 970–980.Google Scholar
Dowling, A. P., Ffowcs Williams, J. E. & Goldstein, M. E. 1978 Sound production in a moving stream. Phil. Trans. R. Soc. Lond. A 288, 321–349.Google Scholar
Ffowcs Williams, J. E. 1982 Boundary-layer pressures and the Corcos model: a development to incorporate low-wavenumber constraints. J. Fluid Mech. 125, 9–25.Google Scholar
Ffowcs Williams, J. E. & Hawkings, D. L. 1969 Sound generation by turbulence and surfaces in arbitrary motion. Phil. Trans. R. Soc. Lond. A 264, 312–342.Google Scholar
Guo, Y. P. 1987 Waves induced by sources near the ocean surface. J. Fluid Mech. 181, 293–310.Google Scholar
Howe, M. S. 1985 On the production of sound by turbulent boundary layer flow over a compliant coating. IMA J. Appl. Maths 33, 189–203.Google Scholar
Hughes, B. 1976 Estimates of underwater sound (and infrasound) produced by non-linearly interacting ocean waves. J. Acoust. Soc. Am. 60, 1032–1039.Google Scholar
Jones, D. S. 1982 The Theory of Generalised Functions. Cambridge University Press.
Lighthill, J. M. 1952 On sound generated aerodynamically. 1. General theory. Proc. R. Soc. Lond. A 221, 564–587.Google Scholar
Phillips, O. M. 1977 The Dynamics of the Upper Ocean. Cambridge University Press.
Urick, R. J. 1967 Principles of Underwater Sound. McGraw-Hill.