"H-states'': exact solutions for a rotating hollow vortex
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Accepted version
Author(s)
Crowdy, Darren
Nelson, Rhodri
Krishnamurthy, Vikas
Type
Journal Article
Abstract
Exact solutions are found for an N-fold rotationally symmetric, steadily rotating hollow vortex where a continuous real parameter governs its deformation from a circular shape and N≥2 is an integer. The vortex shape is found as part of the solution. Following the designation ‘V-states’ assigned to steadily rotating vortex patches (Deem & Zabusky, Phys. Rev. Lett., vol. 40, 1978, pp. 859–862) we call the analogous rotating hollow vortices ‘H-states’. Unlike V-states where all but the N=2 solution – the Kirchhoff ellipse – must be found numerically, it is shown that all H-state solutions can be written down in closed form. Surface tension is not present on the boundaries of the rotating H-states but the latter are shown to be intimately related to solutions for a non-rotating hollow vortex with surface tension on its boundary (Crowdy, Phys. Fluids, vol. 11, 1999a, pp. 2836–2845). It is also shown how the results here relate to recent work on constant-vorticity water waves (Hur & Wheeler, J. Fluid Mech., vol. 896, 2020, R1) where a connection to classical capillary waves (Crapper, J. Fluid Mech., vol. 2, 1957, pp. 532–540) is made.
Date Issued
2021-04-25
Date Acceptance
2021-01-12
Citation
Journal of Fluid Mechanics, 2021, 913, pp.R5-1-R5-11
ISSN
0022-1120
Publisher
Cambridge University Press
Start Page
R5-1
End Page
R5-11
Journal / Book Title
Journal of Fluid Mechanics
Volume
913
Copyright Statement
© The Author(s), 2021. Published by Cambridge University Press. This paper has been accepted for publication and will appear in a revised form, subsequent to peer-review and/or editorial input by Cambridge University Press.
Subjects
01 Mathematical Sciences
09 Engineering
Fluids & Plasmas
Publication Status
Published
Date Publish Online
2021-03-01