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Substructures in a turbulent spot

Published online by Cambridge University Press:  21 April 2006

R. Sankaran,
M. Sokolov and
R. A. Antonia
R. Sankaran
Affiliation:
Department of Mechanical Engineering, University of Newcastle, New South Wales, 2308, Australia
M. Sokolov
Affiliation:
Department of Fluid Mechanics & Heat Transfer, Tel Aviv University, Tel Aviv, 69978, Israel
R. A. Antonia
Affiliation:
Department of Mechanical Engineering, University of Newcastle, New South Wales, 2308, Australia
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Abstract

Substructures within a turbulent spot which develops in a slightly heated laminar boundary layer have been identified using arrays of cold wires aligned in either a streamwise direction or in a direction normal to the wall. At any given streamwise distance from the spot origin, histograms of the number of detected substructures exhibit a peak, defining the most probable spot or the spot with the most likely number of substructures. The number of substructures in the most probable spot increases with streamwise distance but all substructures are convected at approximately the same velocity for any given distance from the wall. This velocity is approximately equal to that of the leading edge of the spot and increases slightly with distance from the wall. The increase in the number of substructures accounts for the streamwise growth of the spot. A simple relation is derived for determining the number of substructures at a particular streamwise station and a geometrical construction is proposed for identifying the origin of a new substructure. There is sufficient evidence for suggesting that the new substructures are formed near the trailing edge of the spot. The convection velocity, inclination and lengthscales of the substructures compare favourably with the corresponding characteristics of hairpin vortices.

Information

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 197 , December 1988, pp. 389 - 414
Copyright
© 1988 Cambridge University Press

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References

Acarlar, M. S. & Smith, C. B.1987a A study of hairpin vortices in a laminar boundary layer. Part 1. Hairpin vortices generated by a hemisphere protruberance. J. Fluid Mech. 175, 1–41.Google Scholar
Acalar, M. S. & Smith, C. R.1987b A study of hairpin vortices in a laminar boundary layer. Part 2. Hairpin vortices generated by fluid injection. J. Fluid Mech. 175, 43–83.Google Scholar
Antonia, R. A., Chambers, A. J. & Sankaran, R.1985 A low speed wind tunnel to study the structure of a boundary layer with pressure gradient. Rep. T.N. - FM 85.1. Department of Mechanical Engineering, University of Newcastle.
Antonia, R. A., Chambers, A. J., Sokolov, M. & Van Atta, C. W. 1981 Simultaneous temperature and velocity measurements in the plane of symmetry of a transitional turbulent spot. J. Fluid Mech. 108, 317–343.Google Scholar
Bandyopadhyay, P. R.1983 Turbulence spot-like features of a boundary layer. Ann. N. Y. Acad. Sci. 404, 393–395.Google Scholar
Biringen, S.1984 Final stages of transition to turbulence in a plane channel flow. J. Fluid Mech. 148, 413–442.Google Scholar
Cantwell, B., Coles, D. & Dimotakis, P.1978 Structure and entrainment in the plane of symmetry of a turbulent spot. J. Fluid Mech. 87, 641–672.Google Scholar
Carlson, D. R., Widnall, S. E. & Peeters, M. F.1982 A flow-visualization study of transition in plane Poiseuille flow. J. Fluid Mech. 121, 487–505.Google Scholar
Chen, C.-H. P. & Blackwelder, R. F. 1978 Large-scale motion in a turbulent boundary layer: a study using temperature contamination. J. Fluid Mech. 89, 1–31.Google Scholar
Elder, J. W.1960 An experimental investigation of turbulent spots and breakdown to turbulence. J. Fluid Mech. 9, 235–246.Google Scholar
Falco, R. E.1977 Coherent motions in the outer region of turbulent boundary layers. Phys. Fluids 20, S124–S132.Google Scholar
Fleischmann, S. T. & Wallace, J. M.1984 Mean streamwise spacing of organized structures in transitional and developed bounded turbulent flows. AIAA J. 22, 766–769.Google Scholar
Fulachier, L., Benabid, T., Anselmet, F., Antonia, R. A. & Krishnamoorthy, L. V. 1987 Behaviour of coherent structures in a turbulent boundary layer with wall suction. In Advances in Turbulence (ed. G. Comte-Bellot & J. Mathieu), pp. 399–407. Springer.
Gad-El-Hak, M., Blackwelder, R. F. & Riley, J. J. 1980 A visual study of the growth and entrainment of turbulent spots. In Laminar—Turbulent Transition (ed. R. Eppler & H. Fasel), pp. 297–310. Springer.
Gad-El-Hak, M., Blackwelder, R. F. & Riley, J. J. 1981 On the growth of turbulent regions in laminar boundary layers. J. Fluid Mech. 110, 73–95.Google Scholar
Gad-El-Hak, M., Blackwelder, R. F. & Riley, J. J. 1985 Visualization techniques for studying transitional and turbulent flows. In Flow Visualization III (ed. W. J. Yang), pp. 568–575. Hemisphere.
Gutmark, E. & Blackwelder, R. F.1987 On the structure of a turbulent spot in a heated laminar boundary layer. Expts Fluids 5, 217–229.Google Scholar
Head, M. R. & Bandyopadhyay, P.1981 New aspects of turbulent boundary-layer structure. J. Fluid Mech. 107, 297–338.Google Scholar
Itsweire, E. C. & Van Atta, C. W. 1984 An experimental investigation of coherent substructures associated with turbulent spots in a laminar boundary layer. J. Fluid Mech. 148, 319–349.Google Scholar
Johansson, A. V., Her, J.-Y. & Haritonidis, J. H. 1987 On the generation of high-amplitude wall-pressure peaks in turbulent boundary layers and spots. J. Fluid Mech. 175, 119–142.Google Scholar
Kim, H. T., Kline, S. J. & Reynolds, W. C.1971 The production of turbulence near a smooth wall in a turbulent boundary layer. J. Fluid Mech. 50, 133–160.Google Scholar
Kline, S. J., Reynolds, W. C., Schraub, F. A. & Runstadler, P. W. 1967 The structure of turbulent boundary layers. J. Fluid Mech. 30, 741–773.Google Scholar
Leonard, A.1980 Vortex simulation of three-dimensional spotlike disturbances in a laminar boundary layer. In Turbulent Shear Flows II (ed. L. J. S. Bradbury, F. Durst, B. E. Launder, F. W. Schmidt & J. H. Whitelaw), pp. 67–77. Springer.
Matsui, T.1980 Visualization of turbulent spots in the boundary layer along a flat plate in a water flow. In Laminar—Turbulent Transition (ed. R. Eppler & H. Fasel), pp. 288–296. Springer.
Mautner, T. S. & Van Atta, C. W. 1986 Wall shear stress measurements in the plane of symmetry of a turbulent spot. Expts Fluids 4, 153–162.Google Scholar
Motohashi, T. & Blackwelder, R. F.1983 Decreasing the side wall contamination in wind tunnels. Trans. ASME I: J. Fluids Engng 105, 435–438.Google Scholar
Perry, A. E. & Chong, M. S.1982 On the mechanism of wall turbulence. J. Fluid Mech. 119, 173–217.Google Scholar
Perry, A. E., Lim, T. T., Chong, M. S. & Teh, E. W. 1980 The fabric of turbulence. AIAA Paper 80–1358 (presented at AIAA 13th Fluid and Plasma Dynamics Conference, Snowmass, CO).Google Scholar
Perry, A. E., Lim, T. T. & Teh, E. W.1981 A visual study of turbulent spots. J. Fluid Mech. 104, 387–405.Google Scholar
Riley, J. J. & Gad-el-Hak, M. 1985 The dynamics of turbulent spots. In Frontiers in Fluid Mechanics (ed. S. H. Davis & J. L. Lumley), pp. 123–155. Springer.
Rogers, M. M. & Moin, P.1987 The structure of the vorticity field in homogeneous turbulent flows. J. Fluid Mech. 176, 33–66.Google Scholar
Sankaran, R. & Antonia, R. A.1988 The influence of a favourable pressure gradient on the growth of a turbulent spot. AIAA J. (To appear.)Google Scholar
Sankaran, R., Chambers, A. J. & Antonia, R. A.1986 The influence of a favourable pressure gradient on the growth of a turbulent spot. In Proc. 9th Australian Fluid Mechanics Conf., Auckland, pp. 342–345.Google Scholar
Schubauer, G. B. & Klebanoff, P. S.1956 Contributions on the mechanics of boundary-layer transition. NACA Rep. 1289.Google Scholar
Smith, C. R. & Metzler, S. P. 1983 The characteristics of low-speed streaks in the near-wall region of a turbulent boundary layer. J. Fluid Mech. 129, 27–54.Google Scholar
Smith, C. R. & Schwartz, S. P.1983 Observation of streamwise rotation in the near-wall region of a turbulent boundary layer. Phys. Fluids 26, 641–652.Google Scholar
Sokolov, M., Antonia, R. A. & Chambers, A. J.1980 A similarity transformation for a turbulent spot in a laminar boundary layer. Phys. Fluids 23, 2561–2563.Google Scholar
Sokolov, M., Antonia, R. A. & Chambers, A. J.1986 A turbulent spot in a two-dimensional duct. J. Fluid Mech. 166, 211–226.Google Scholar
Subramanian, C. S., Rajagopalan, S., Antonia, R. A. & Chambers, A. J. 1982 Comparison of conditional sampling and averaging techniques in a turbulent boundary layer. J. Fluid Mech. 123, 335–362.Google Scholar
Townsend, A. A.1956 The Structure of Turbulent Shear Flow, 1st edn. Cambridge University Press.
Wallace, J. M.1982 On the structure of bounded turbulent shear flow: a personal view. In Developments in Theoretical and Applied Mechanics XI (ed. T. J. Chung), pp. 509–521. Department of Mechanical Engineering, University of Alabama-Huntsville.
Wygnanski, I.1983 On turbulent spots. In Symp. on Turbulence: Proc. Seventh Symposium on Turbulence, September 1981 (ed. G. K. Patterson & J. L. Zakin), pp. 390–400. University of Missouri-Rolla.
Wygnanski, I., Haritonidis, J. H. & Kaplan, R. E.1979 On a Tollmien—Schlichting wave packet produced by a turbulent spot. J. Fluid Mech. 92, 505–528.Google Scholar
Wygnanski, I., Sokolov, M. & Friedman, D.1976 On a turbulent ‘spot’ in a laminar boundary layer. J. Fluid Mech. 78, 785–819.Google Scholar
Wygnanski, I., Zilberman, M. & Haritonidis, J. H.1982 On the spreading of turbulent spot in the absence of a pressure gradient. J. Fluid Mech. 123, 69–90.Google Scholar