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arXiv · 1509.00813

Dissipation of Quasiclassical Turbulence in Superfluid $^4$He

D. E. Zmeev·P. M. Walmsley·A. I. Golov·P. V. E. McClintock·S. N. Fisher·W. F. Vinen
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Abstract

We compare the decay of turbulence in superfluid $^4$He produced by a moving grid to the decay of turbulence created by either impulsive spin-down to rest or by intense ion injection. In all cases the vortex line density $L$ decays at late time $t$ as $L \propto t^{-3/2}$. At temperatures above 0.8 K, all methods result in the same rate of decay. Below 0.8 K, the spin-down turbulence maintains initial rotation and decays slower than grid turbulence and ion-jet turbulence. This may be due to a decoupling of the large-scale superfluid flow from the normal component at low temperatures, which changes its effective boundary condition from no-slip to slip.

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D. E. Zmeev, P. M. Walmsley, A. I. Golov, P. V. E. McClintock, S. N. Fisher, W. F. Vinen. 2015-09-02. Dissipation of Quasiclassical Turbulence in Superfluid $^4$He. https://doi.org/10.1103/physrevlett.115.155303

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