dc.contributor.author | Bassom, Andrew P. | en_GB |
dc.contributor.author | Gilbert, Andrew D. | en_GB |
dc.contributor.department | University of Exeter | en_GB |
dc.date.accessioned | 2009-03-18T15:12:05Z | en_GB |
dc.date.accessioned | 2011-01-25T10:33:45Z | en_GB |
dc.date.accessioned | 2013-03-20T12:28:39Z | |
dc.date.issued | 1998 | en_GB |
dc.description.abstract | The relaxation of a smooth two-dimensional vortex to axisymmetry, also known as `axisymmetrization', is studied asymptotically and numerically. The vortex is perturbed at t = 0 and differential rotation leads to the wind-up of vorticity fluctuations to forma spiral. It is shown that for infinite Reynolds number and in the linear approximation, the vorticity distribution tends to axisymmetry in a weak or coarse-grained sense: when the vorticity field is integrated against a smooth test function the result decays asymptotically as t−λ with λ = 1 + (n2 + 8)1/2, where n is the azimuthal wavenumber of the perturbation and n ≥1. The far-field stream function of the perturbation decays with the same exponent. To obtain these results the paper develops a complete asymptotic picture of the linear evolution of vorticity fluctuations for large times t, which is based on that of Lundgren (1982). | en_GB |
dc.identifier.citation | Vol. 371, pp. 109-140 | en_GB |
dc.identifier.doi | 10.1017/S0022112098001955 | en_GB |
dc.identifier.uri | http://hdl.handle.net/10036/56333 | en_GB |
dc.language.iso | en | en_GB |
dc.publisher | Cambridge University Press | en_GB |
dc.relation.url | http://www.journals.cambridge.org/abstract_S0022112098001955 | en_GB |
dc.title | The spiral wind-up of vorticity in an inviscid planar vortex | en_GB |
dc.type | Article | en_GB |
dc.date.available | 2009-03-18T15:12:05Z | en_GB |
dc.date.available | 2011-01-25T10:33:45Z | en_GB |
dc.date.available | 2013-03-20T12:28:39Z | |
dc.identifier.issn | 0022-1120 | en_GB |
dc.identifier.issn | 1469-7645 | en_GB |
dc.description | Copyright © 1998 Cambridge University Press. Published version reproduced with the permission of the publisher. | en_GB |
dc.identifier.journal | Journal of Fluid Mechanics | en_GB |