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An optical interferometric study of the wake of a bluff body

Published online by Cambridge University Press:  26 April 2006

R. B. Green
Affiliation:
Department of Engineering, University of Manchester, Manchester M13 9PL, UK
J. H. Gerrard
Affiliation:
Department of Engineering, University of Manchester, Manchester M13 9PL, UK

Abstract

A Fizeau optical interferometer has been used to visualize the wake behind a circular cylinder at low Reynolds numbers Re. As well as showing the vortex shedding mechanism and development of the far wake in a new light, the shed vortex strength and age were derived from the results. The vortex velocity distributions, at downstream distances of 5 to 16 diameters, were found to be those of convected Oseen vortices. These measurements confirmed the existence of a transition at Re ≈ 100, which reflects the emergence of convection as the dominant process in the near wake.

Type
Research Article
Copyright
© 1991 Cambridge University Press

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