Zmeev, Dmitriy E. and Walmsley, P. M. and Golov, A. I. and McClintock, Peter V. E. and Fisher, Shaun N. and Vinen, W. F. (2015) Dissipation of quasiclassical turbulence in superfluid 4He. Physical review letters, 115 (15): 155303. ISSN 1079-7114
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Abstract
We compare the decay of turbulence in superfluid 4He produced by a moving grid to the decay of urbulence 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 approximately as L / -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.