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The instantaneous velocity fields of coherent structures in coflowing jets and wakes

Published online by Cambridge University Press:  19 April 2006

A. E. Perry
Affiliation:
Department of Mechanical Engineering, University of Melbourne, Parkville, Victoria, Australia
T. T. Lim
Affiliation:
Department of Mechanical Engineering, University of Melbourne, Parkville, Victoria, Australia
M. S. Chong
Affiliation:
Department of Mechanical Engineering, University of Melbourne, Parkville, Victoria, Australia

Abstract

The instantaneous velocity vector fields which surround the coherent structures of Perry & Lim (1978) in coflowing jets and wakes have been successfully measured and related to the smoke patterns for Reynolds numbers of order 1000. By the use of critical point theory, a qualitative description of the three-dimensional flow field can be made and is applied to the simplest structures which were classified by Perry & Lim. From these results, the convection of smoke and vorticity from the source and the entrainment properties of the structures are discussed.

Type
Research Article
Copyright
© 1980 Cambridge University Press

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References

Achenbach, E. 1974 J. Fluid Mech. 62, 209.
Brown, G. L. & Roshko, A. 1974 J. Fluid Mech. 64, 775.
Cantwell, B. J. 1975 A flying hot-wire study of the turbulent near wake of a circular cylinder at a Reynolds number of 140000. Ph.D. thesis. Cal. Inst. of Tech.
Cantwell, B. J. 1978 J. Fluid Mech. 85, 257.
Cantwell, B. J., Coles, D. & Dimotakis, P. 1978 J. Fluid Mech. 87, 641.
Corcos, G. M. & Sherman, F. S. 1976 J. Fluid Mech. 73, 241.
Davey, A. 1961 J. Fluid Mech. 10, 593.
Davies, P. O. A. L. & Yule, A. J. 1975 J. Fluid Mech. 69, 513.
Falco, R. E. 1977 Phys. Fluids vol. 20. No. 10 Pt. II, p. 124.
Head, M. R. 1960 Aero. Res. Counc. R. & M. 3152.
Head, M. R. & Bradshaw, P. 1971 J. Fluid Mech. 46, 385.
Hunt, J. C. R., Abell, C. J., Peterka, J. A. & Woo, H. 1978 J. Fluid Mech. 86, 179.
Lighthill, M. J. 1963 In Laminar Boundary Layers (ed. L. Rosenhead), pp. 4888. Clarendon.
Lim, T. T. 1979 Coherent structures in coflowing jets and wakes. Ph.D. thesis, University of Melbourne.
Oswatitsch, K. 1958 In Die Ablonsungsbedingung von Grenzschichten. Grenzschicht Forschung (ed. H. Goertler), p. 357. Springer.
Perry, A. E. & Fairlei, B. D. 1974 Adv. Geophys. B 18, 299.
Perry, A. E. & Fairlie, B. D. 1975 J. Fluid Mech. 69, 657.
Perry, A. E. & Lim, T. T. 1978 J. Fluid Mech. 88, 451.
Perry, A. E. & Watmuff, J. H. 1981 J. Fluid Mech. (to appear).
Roshko, A. 1954 N.A.C.A. Rep. no. 1191.
Smith, J. H. B. 1972 Prog. Aero. Sci. 12, 241.
Taneda, S. 1978 J. Fluid Mech. 85, 187.
Winant, C. D. & Browand, F. K. 1974 J. Fluid Mech. 63, 237.