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The formation and maintenance of a leading-edge vortex during the forward motion of an animal wing

Published online by Cambridge University Press:  28 August 2007

T. MAXWORTHY*
Affiliation:
Department of Aerospace and Mechanical Engineering, University of Southern California, Los Angeles CA 90089, USA

Abstract

A simple model is presented to explain the observed generation of a quasi-steady vortex at the leading edge of an animal wing that rotates in a horizontal plane about a body-centred axis. Vorticity formed by separation at the leading edge is transported outwards by a spanwise velocity field generated by two sources of spanwise pressure gradient, one induced centrifugally and the other by variations in the vortex size and circulation. The vorticity is then deposited into a trailing vortex system that takes the form of a downward propagating vortex ring. This mechanism appears to apply generally to flying animals but is modelled here for those in hovering flight.

Type
Papers
Copyright
Copyright © Cambridge University Press 2007

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References

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