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arXiv · 1610.03690

Large-scale normal fluid circulation in helium superflows

Luca Galantucci·Michele Sciacca·Carlo F. Barenghi
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Abstract

We perform fully-coupled numerical simulations of helium II pure superflows in a channel, with vortex- line density typical of experiments. Peculiar to our model is the computation of the back-reaction of the superfluid vortex motion on the normal fluid and the presence of solid boundaries. We recover the uniform vortex-line density experimentally measured employing second sound resonators and we show that pure superflow in helium II is associated with a large-scale circulation of the normal fluid which can be detected using existing particle-tracking visualization techniques.

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Luca Galantucci, Michele Sciacca, Carlo F. Barenghi. 2016-10-12. Large-scale normal fluid circulation in helium superflows. https://doi.org/10.1103/physrevb.95.014509

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