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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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