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Vortex Motion in a Weak Background Shear Flow
journal contribution
posted on 2023-05-18, 17:34 authored by Bajer, K, Andrew BassomAndrew Bassom, Gilbert, ADA point vortex is introduced into a weak background vorticity gradient at finite Reynolds number. As the vortex spreads viscously so the background vorticity becomes wrapped around it, leading to enhanced diffusion of vorticity, but also giving a feedback on the vortex and causing it to move. This is investigated in the linear approximation, using a similarity solution for the advection of weak vorticity around the vortex, at finite and infinite Reynolds number. A logarithmic divergence in the far field requires the introduction of an outer length scale L and asymptotic matching. In this way results are obtained for the motion of a vortex in a weak vorticity field modulated on the large scale L and these are confirmed by means of numerical simulations.
History
Publication title
Journal of Fluid MechanicsVolume
509Pagination
281-304ISSN
0022-1120Department/School
School of Natural SciencesPublisher
Cambridge Univ PressPlace of publication
40 West 20Th St, New York, USA, Ny, 10011-4211Rights statement
Copyright 2004 Cambridge University PressRepository Status
- Restricted