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arXiv · 1603.06403

Leapfrogging Kelvin waves

N. Hietala·R. Hänninen·H. Salman·C. F. Barenghi
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Abstract

Two vortex rings can form a localized configuration whereby they continually pass through one another in an alternating fashion. This phenomenon is called leapfrogging. Using parameters suitable for superfluid helium-4, we describe a recurrence phenomenon that is similar to leapfrogging, which occurs for two coaxial straight vortex filaments with the same Kelvin wave mode. For small-amplitude Kelvin waves we demonstrate that our full Biot-Savart simulations closely follow predictions obtained from a simpified model that provides an analytical approximation developed for nearly parallel vortices. Our results are also relevant to thin-cored helical vortices in classical fluids.

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N. Hietala, R. Hänninen, H. Salman, C. F. Barenghi. 2016-11-22. Leapfrogging Kelvin waves. https://doi.org/10.1103/physrevfluids.1.084501

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