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arXiv · 1908.01507

Observation of the resonance frequencies of a stable torus of fluid

Claude Laroche·Jean-Claude Bacri·Martin Devaud·Timothée Jamin·Eric Falcon
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Abstract

We report the first quantitative measurements of the resonance frequencies of a torus of fluid confined in a horizontal Hele-Shaw cell. By using the unwetting property of a metal liquid, we are able to generate a stable torus of fluid with an arbitrary aspect ratio. When subjected to vibrations, the torus displays azimuthal patterns at its outer periphery. These lobes oscillate radially, and their number n depends on the forcing frequency. We report the instability ''tongues'' of the patterns up to n = 25. These resonance frequencies are well explained by adapting to a fluid torus the usual drop model of Lord Rayleigh. This approach could be applied to the modeling of large-scale structures arisen transiently in vortex rings in various domains.

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Claude Laroche, Jean-Claude Bacri, Martin Devaud, Timothée Jamin, Eric Falcon. 2019-08-05. Observation of the resonance frequencies of a stable torus of fluid. https://doi.org/10.1103/physrevlett.123.094502

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