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Artificial control of the laminar-turbulent transition of a two-dimensional wake by external sound

Published online by Cambridge University Press:  12 April 2006

Hiroshi Sato  and
Hironosuke Saito
Hiroshi Sato
Affiliation:
Institute of Space and Aeronautical Science, University of Tokyo, Japan
Hironosuke Saito
Affiliation:
Institute of Space and Aeronautical Science, University of Tokyo, Japan
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Abstract

Artificial acceleration and deceleration of the transition process in a two-dimensional wake were attempted. The wake was produced behind a thin aerofoil placed parallel to uniform flow. The sound from a loudspeaker introduced into the wake acted as an artificial disturbance. Various kinds of sound were tested and the effect on the transition was judged by the energy spectrum. Sinusoidal sound of the frequency of the maximum growth rate in the linear region decelerates the transition, whereas sound of a different frequency accelerates it. Sound of two or four frequencies is more effective in accelerating the transition when the frequencies are properly chosen. White noise from the loudspeaker is not effective, but a two-peak noise specially designed for strong nonlinear interaction is the most effective in accelerating the transition process. These results can be explained by two empirical properties of the nonlinear interaction: the growth suppression induced by a large amplitude fluctuation and the stronger interaction between fluctuations of closer amplitudes.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 84 , Issue 4 , 27 February 1978 , pp. 657 - 672
Copyright
© 1978 Cambridge University Press

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References

Klebanoff, P. S., Tidstrom, K. D. & Sargent, L. M. 1962 The three-dimensional nature of boundary-layer instability. J. Fluid Mech. 12, 1.Google Scholar
Ko, D. R., Kubota, T. & Lees, L. 1970 Finite disturbance effect on the stability of a laminar incompressible wake behind a flat plate. J. Fluid Mech. 40, 315.Google Scholar
Mattingly, G. E. & Criminale, W. O. 1972 The stability of an incompressible two-dimensional wake. J. Fluid Mech. 51, 233.Google Scholar
Nakaya, C. 1976 Instability of the near wake behind a circular cylinder. J. Phys. Soc. Japan 41, 1087.Google Scholar
Sato, H. 1970 An experimental study of non-linear interaction of velocity fluctuations in the transition region of a two-dimensional wake. J. Fluid Mech. 44, 741.Google Scholar
Sato, H. & Kuriki, K. 1961 The mechanism of transition in the wake of a thin flat plate placed parallel to a uniform flow. J. Fluid Mech. 11, 321.Google Scholar
Sato, H. & Saito, H. 1975 Fine-structure of energy spectra of velocity fluctuations in the transition region of a two-dimensional wake. J. Fluid Mech. 67, 539.Google Scholar
Zabusky, N. J. & Deem, G. S. 1971 Dynamical evolution of two-dimensional unstable shear flows. J. Fluid Mech. 47, 353.Google Scholar