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Vortex shedding from slender cones at low Reynolds numbers

Published online by Cambridge University Press:  26 April 2006

A. Papangelou
Affiliation:
Department of Engineering, University of Cambridge. Trumpineton Street. Cambridge CB2 1PZ, UK

Abstract

Wind-tunnel experiments on the flows created by a number of slightly tapered models of circular cross-section have shown the presence of spanwise cells (regions of constant shedding frequency) at Reynolds numbers of the order of 100. The experiments have also shown a number of other interesting features of these flows: the cellular flow configuration is dependent on the base Reynolds number and independent of the tip Reynolds number, the frequency jump between adjacent cells is a function of flow speed, taper angle and kinematic viscosity, but is constant along a cone's span, and the unsteady hot-wire anemometer signal is both amplitude and phase modulated. A mathematical model is proposed based on the complex Landau—Stuart equation with a spanwise diffusive coupling term. Numerical solutions of this equation have shown many of the qualitative features observed in the experiments.

Type
Research Article
Copyright
© 1992 Cambridge University Press

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