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arXiv · 0709.0368

Vortex spectrum in superfluid turbulence: interpretation of a recent experiment

Philippe-Emmanuel P. -E. Roche·Carlo F. Barenghi
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Abstract

We discuss a recent experiment in which the spectrum of the vortex line density fluctuations has been measured in superfluid turbulence. The observed frequency dependence of the spectrum, $f^{-5/3}$, disagrees with classical vorticity spectra if, following the literature, the vortex line density is interpreted as a measure of the vorticity or enstrophy. We argue that the disagrement is solved if the vortex line density field is decomposed into a polarised field (which carries most of the energy) and an isotropic field (which is responsible for the spectrum).

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Philippe-Emmanuel P. -E. Roche, Carlo F. Barenghi. 2007-09-04. Vortex spectrum in superfluid turbulence: interpretation of a recent experiment. https://doi.org/10.1209/0295-5075/81/36002

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