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Three-dimensional vortex structure on a rotating wing

Published online by Cambridge University Press:  06 August 2012

Cem A. Ozen
Affiliation:
Department of Mechanical Engineering & Mechanics, Lehigh University, Bethlehem, PA 18015, USA
D. Rockwell*
Affiliation:
Department of Mechanical Engineering & Mechanics, Lehigh University, Bethlehem, PA 18015, USA
*
Email address for correspondence: dor0@lehigh.edu

Abstract

The three-dimensional structure of the leading-edge vortex on a rotating wing is addressed using a technique of particle image velocimetry. Organized patterns of chordwise-oriented vorticity, which exist within the vortex, arise from the spanwise flow along the surface of the wing, which can attain a velocity the same order as the velocity of the wing at its radius of gyration. These patterns are related to the strength (circulation) and coherence of the tip and root vortices. The associated distributions of spanwise-oriented vorticity along the leading-edge vortex are characterized in relation to the vorticity flux and downwash along the wing.

Type
Papers
Copyright
Copyright © Cambridge University Press 2012

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