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An Experimental and Theoretical Investigation of the Structure of a Trailing Vortex Wake

Published online by Cambridge University Press:  07 June 2016

R G Sampson*
Affiliation:
Royal Military College of Science
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Summary

An improved technique for the use of a five-hole yaw probe has been used in determining velocity, vorticity and pressure distributions over a transverse plane five chords downstream of a lifting wing. A well-defined tip vortex is shown to exist, together with a vortex sheet which contains a significant proportion of the total vorticity. The vorticity distribution is compared with that predicted by the calculation of vortex sheet roll-up using a two-dimensional array of line vortices. Good agreement is obtained, and the validity of using time steps large enough to inhibit the chaotic motion found in some calculations of this type is demonstrated. The structure of the tip vortex is found to be well described by the turbulent vortex model of Hoffman and Joubert.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society. 1977

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