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arXiv · 1901.02215

$^4$He Counterflow Differs Strongly from Classical Flows: Anisotropy on Small Scales

L. Biferale·D. Khomenko·V. L'vov·A. Pomyalov·I. Procaccia·G. Sahoo
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Abstract

Three-dimensional anisotropic turbulence in classical fluids tends towards isotropy and homogeneity with decreasing scales, allowing --eventually-- the abstract model of "isotropic homogeneous turbulence" to be relevant. We show here that the opposite is true for superfluid $^4$He turbulence in 3-dimensional counterflow channel geometry. This flow becomes less isotropic upon decreasing scales, becoming eventually quasi 2-dimensional. The physical reason for this unusual phenomenon is elucidated and supported by theory and simulations.

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L. Biferale, D. Khomenko, V. L'vov, A. Pomyalov, I. Procaccia, G. Sahoo. 2019-01-08. $^4$He Counterflow Differs Strongly from Classical Flows: Anisotropy on Small Scales. https://doi.org/10.1103/physrevlett.122.144501

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