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arXiv · 1805.09005

Mesoscale helicity distinguishes Vinen from Kolmogorov turbulence in helium II

L. Galantucci·C. F. Barenghi·N. G. Parker·A. W. Baggaley
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Abstract

Experiments and numerical simulations show that quantum turbulence exists in two distinct limiting regimes: Kolmogorov turbulence (which shares with classical turbulence the important property of a cascade of kinetic energy from large eddies to small eddies) and Vinen turbulence (which is more similar to a random flow). In this work, we define a mesoscale helicity for the superfluid, which, tested in numerical experiments, distinguishes the two turbulent regimes, quantifying the amount of nonlocal vortex interactions and the orientation of the vortex lines.

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L. Galantucci, C. F. Barenghi, N. G. Parker, A. W. Baggaley. 2018-05-23. Mesoscale helicity distinguishes Vinen from Kolmogorov turbulence in helium II. https://doi.org/10.1103/physrevb.103.144503

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