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A visual study of turbulent spots

Published online by Cambridge University Press:  20 April 2006

A. E. Perry ,
T. T. Lim  and
E. W. Teh
A. E. Perry
Affiliation:
Department of Mechanical Engineering, University of Melbourne, Parkville, Victoria 3052, Australia
T. T. Lim
Affiliation:
Department of Mechanical Engineering, University of Melbourne, Parkville, Victoria 3052, Australia
E. W. Teh
Affiliation:
Department of Mechanical Engineering, University of Melbourne, Parkville, Victoria 3052, Australia
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Abstract

From the results of a flow visualization experiment, certain physical characteristics of a turbulent spot are suggested by the authors. The spot was artificially initiated at a point by a small intermittent wall jet. The authors also carried out experiments behind vibrating trip wires and observed the ‘signatures’ or ‘footprints’ of the A-shaped vortices seen by other workers. The fact that these ‘signatures’ are also observed in a turbulent spot leads one to suspect that these spots consist essentially of an array of A-shaped vortices. The formation of the spot is subsequently described in terms of three-dimensional disturbances of the cross-stream vortex filaments.

The basic structure of the turbulent spot proposed here is similar to the suggested structure of fully developed turbulent boundary layers first put forward by Theodorsen (1955) and more recently by Bandyopadhyay & Head (1979).

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 104 , March 1981 , pp. 387 - 405
Copyright
© 1981 Cambridge University Press

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References

Bandyopadhyay, P. & Head, M. R. 1979 Film: Visual investigation of turbulent boundary structure. Engineering Department, University of Cambridge.
Cantwell, B., Coles, C. & Dimotakis, P. 1978 Structure and entrainment in the plane of symmetry of a turbulent spot. J. Fluid Mech. 87, 641–672.Google Scholar
Coles, C. & Barker, S. J. 1975 Some remarks on a synthetic turbulent boundary layer. In Turbulent Mixing in Nonreactive and Reactive Flows (ed. S. N. B. Murthy), pp. 285–292. Plenum.
Emmons, H. W. 1951 The laminar-turbulent transition in a boundary layer. Part 1. J. Aero. Sci. 18, 490–498.Google Scholar
Falco, R. E. 1977 Coherent motions in the outer regions of turbulent boundary layers. Phys. Fluids Suppl 20, 124–132.Google Scholar
Gaster, M. 1975 A theoretical model of a wave packet in the boundary layer on a flat plate. Proc. Roy. Soc. A 347, 271–289.Google Scholar
Gaster, M. & Grant, I. 1975 An experimental investigation of the formation and development of a wave packet in a laminar boundary layer. Proc. Roy. Soc. A 347, 253–269.Google Scholar
Hama, F. R. & Nutant, J. 1963 Detailed flow-field observations in the transition process in a thick boundary layer. Proc. 1963 Heat Trans. & Fluid Mech. Inst., pp. 77–94. Stanford University Press.
Klebanoff, P. S. & Tidstrom, K. D. 1959 Evolution of amplified waves leading to transition in a boundary layer with zero pressure gradient. N.A.S.A. Tech. Note no. D-195.Google Scholar
Klebanoff, P. S., Tidstrom, K. D. & Sargent, L. M. 1962 The three-dimensional nature of boundary-layer instability. J. Fluid Mech. 12, 1–34.Google Scholar
Kline, S. J. 1967 Observed structural features in turbulent and transitional boundary layers. Fluid Mechanics of Internal Flow (ed. G. Sovran), pp. 27–79. Elsevier.
Kovasznay, L. S. G., Komoda, H. & Vasudeva, B. R. 1962 Detailed flow field in transition. Proc. 1962 Heat Trans. & Fluid Mech. Inst., pp. 1–26. Stanford University Press.
Perry, A. E. & Lim, T. T. 1978 Coherent structures in coflowing jets and wakes. J. Fluid Mech. 88, 451–463.Google Scholar
Schlichting, H. 1979 Boundary-Layer Theory, 7th edn. McGraw-Hill.
Schubauer, G. B. & Klebanoff, P. S. 1956 Contributions on the mechanics of boundary-layer transition. N.A.C.A. Rep. no. 1289.Google Scholar
Schubauer, G. B. & Skramstad, H. K. 1948 Laminar boundary layer oscillations on a flat plate. N.A.C.A. Rep. no. 909.Google Scholar
Theodorsen, T. 1955 The structure of turbulenc 50 Jahre Grenzschichtforschung (ed. H. Görtler & W. Tollmien), p. 55. Braunschweig: Veiweg and Sohn.
Wygnanski, I., Haritonidis, J. H. & Kaplan, R. E. 1979 On a Tollmien-wave packet produced by a turbulent spot. J. Fluid Mech. 92, 505–528.Google Scholar
Wygnanski, I., Sokolov, N. & Friedman, D. 1976 On the turbulent ‘spot’ in laminar boundary layer. J. Fluid Mech. 87, 641–672.Google Scholar