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Near-neutral centre-modes as inviscid perturbations to a trailing line vortex

Published online by Cambridge University Press:  20 April 2006

K. Stewartson  and
S. N. Brown
K. Stewartson
Affiliation:
Department of Mathematics. University College London, Gower Street. London WC1E 6BT
S. N. Brown
Affiliation:
Department of Mathematics. University College London, Gower Street. London WC1E 6BT
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Abstract

Inviscid linear perturbations to a columnar trailing line vortex are found in the form of centre-modes. These near-neutral modes, occurring at moderate values of the azimuthal wavenumber n, are the analogue of the ring modes for large n discussed by Stewartson & Capell (1985). The appearance and disappearance of these modes as the swirl parameter varies may partly explain the difficulties encountered by numerical analysts in the computation of such modes. In addition, instabilities are found at higher values of the swirl parameter than have previously been reported.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 156 , July 1985 , pp. 387 - 399
Copyright
© 1985 Cambridge University Press

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References

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