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Examples of steady vortex rings of small cross-section in an ideal fluid

Published online by Cambridge University Press:  29 March 2006

L. E. Fraenkel
Affiliation:
Department of Applied Mathematics and Theoretical Physics, Cambridge

Abstract

The existence theory for steady vortex rings of small cross-section is used to derive asymptotic formulae that describe the shape and overall properties of such rings. A certain two-parameter family of rings is studied in detail, to a first approximation; for members of this family, the ratio ω/r (of vorticity to cylindrical radius) falls from a positive maximum at a central point of the core cross-section to a value at the core boundary that can be substantially smaller or even negative. The case of uniform ω/r is considered to a higher order of approximation, and the formulae given for this case appear to be useful for quite substantial cross-sections.

Type
Research Article
Copyright
© 1972 Cambridge University Press

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References

Dyson, F. W. 1893 The potential of an anchor ring, I and II. Phil. Trans. Roy. Soc. A 184, 43 and 1041.Google Scholar
Fraenkel, L. E. 1969 On the method of matched asymptotic expansions, III. Proc. Camb. Phil. Soc. 65, 263.Google Scholar
Fraenkel, L. E. 1970 On steady vortex rings of small cross-section in an ideal fluid. Proc. Roy. Soc. A 316, 29.Google Scholar
Lamb, H. 1932 Hydrodynamics. Cambridge University Press.
Maruhn, K. 1934 Über zwei Gleichgewichtsfiguren rotierender inhomogener Flüssigkeit. Math. Zschr. 39, 244.Google Scholar
Maruhn, K. 1957 Über die Existenz stationärer Bewegungen von Wirbelringen. Proc. Ninth International Congress Appl. Mech. Brussels, 1, 173.Google Scholar
Norbury, J. 1972a A steady vortex ring close to Hill's spherical vortex. To appear in Proc. Camb. Phil. Soc.Google Scholar
Norbury, J. 1972b A family of steady vortex rings. To be submitted to J. Fluid Mech.Google Scholar
Saffman, P. G. 1970 The velocity of viscous vortex rings. Studies in Appl. Math. 49, 371.Google Scholar