Abstract
The spectral levels of the quadrupole noise generated by a boundary layer flow over a smooth surface are calculated. Explicit dependences of the noise levels on the Reynolds number are obtained for the low-frequency and high-frequency ranges. It is shown that the logarithmic zone of the velocity profile is responsible for the region of the quadrupole noise spectrum with a hyperbolic dependence on frequency. A method of calculating the dipole noise of a boundary layer flow over a rough surface is developed. The method is based on the use of the combined probability density for the turbulent velocity fluctuations and the random dimensions of protuberances of the rough surface. The two constants involved in this theory are determined from a special experiment. It is shown that the surface roughness noticeably increases the radiation levels of a boundary layer flow in a certain frequency range.
Similar content being viewed by others
References
J. E. Ffowcs Williams, J. Sound Vibr. 190, 387 (1996).
A. V. Smol’yakov, Akust. Zh. 19, 251 (1973) [Sov. Phys. Acoust. 19, 65 (1973)].
A. V. Smol’yakov, Akust. Zh. 19, 420 (1973) [Sov. Phys. Acoust. 19, 271 (1973)].
W. K. Blake, Mechanics and Flow-Induced Sound and Vibration (Academic, New York, 1986).
M. I. Rabinovich, V. P. Reutov, and G. V. Rybushkina, Akust. Zh. 30, 105 (1984) [Sov. Phys. Acoust. 30, 60 (1984)].
M. S. Howe, J. Sound Vibr. 104, 29 (1986).
M. S. Howe, Proc. R. Soc. London, Ser. A 415, 141 (1988).
A. V. Smol’yakov, Akust. Zh. 46, 401 (2000) [Acoust. Phys. 46, 342 (2000)].
J. O. Hinze, Turbulence, an Introduction to Its Mechanism and Theory (McGraw-Hill, New York, 1959; Fizmatlit, Moscow, 1963).
H. Schlichting, Grenzschicht-Theorie (G. Braun, Karlsruhe, 1965; McGraw-Hill, New York, 1968; Nauka, Moscow, 1974).
A. G. Munin, V. M. Kuznetsov, and E. A. Leont’ev, Aerodynamical Sources of Sound (Mashinostroenie, Moscow, 1981).
P. Bradshaw, J. Fluid Mech. 30, 241 (1967).
W. L. Keith, D. A. Hurdis, and B. M. Abraham, J. Fluids Eng. 114, 338 (1992).
J. E. Ffowcs Williams and L. H. Hall, J. Fluid Mech. 70, 657 (1970).
M. S. Howe, J. Sound Vibr. 65, 159 (1979).
A. V. Smol’yakov, Akust. Zh. 35, 506 (1989) [Sov. Phys. Acoust. 35, 296 (1989)].
A. V. Smol’yakov, Acustica 80, 541 (1994).
G. Korn and T. Korn, Mathematical Handbook for Scientists and Engineers, 2nd ed. (McGraw-Hill, New York, 1961; Nauka, Moscow, 1968).
A. V. Smol’yakov and V. M. Tkachenko, Akust. Zh. 37, 1199 (1991) [Sov. Phys. Acoust. 37, 627 (1991)].
G. M. Corcos, J. Acoust. Soc. Am. 35, 192 (1963).
A. V. Smol’yakov and V. M. Tkachenko, The Measurement of Turbulent Fluctuations (Énergiya, Leningrad, 1980; Springer-Verlag, Berlin, 1983).
V. K. Iofe, V. G. Korol’kov, and M. A. Sapozhkov, A Handbook on Acoustics (Svyaz’, Moscow, 1979).
L. G. Loitsyanskii, Fluid Mechanics (Fizmatlit, Moscow, 1973).
Author information
Authors and Affiliations
Additional information
__________
Translated from Akusticheski\(\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\smile}$}}{l}\) Zhurnal, Vol. 47, No. 2, 2001, pp. 264–272.
Original Russian Text Copyright © 2001 by Smol’yakov.
Rights and permissions
About this article
Cite this article
Smol’yakov, A.V. Noise of a turbulent boundary layer flow over smooth and rough plates at low mach numbers. Acoust. Phys. 47, 218–225 (2001). https://doi.org/10.1134/1.1355808
Received:
Issue Date:
DOI: https://doi.org/10.1134/1.1355808