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Unsteady lifting-line theory by the method of matched asymptotic expansions

Published online by Cambridge University Press:  21 April 2006

P. Wilmott
P. Wilmott
Affiliation:
Department of Mathematics, Imperial College, London SW7 2BZ, UK
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Abstract

An unsteady lifting-line theory is presented for a general motion of a wing of high aspect ratio. Our matched-asymptotic-expansions analysis parallels that of Van Dyke (1964) in his solution for the steady lifting line, but is complicated by the shedding of transverse vortices associated with variation of circulation with time. The principal result is an expression for the downwash due to three-dimensional effects. Numerical calculations are presented for a wing of elliptic planform following a curved path.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 186 , January 1988 , pp. 303 - 320
Copyright
© 1988 Cambridge University Press

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