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arXiv · 1008.4378

The saturation of decaying counterflow turbulence in helium II

Michele Sciacca·Yuri A. Sergeev·Carlo F. Barenghi·Ladik Skrbek
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Abstract

We are concerned with the problem of the decay of a tangle of quantized vortices in He II generated by a heat current. Direct application of Vinen's equation yields the temporal scaling of vortex line density $L \sim t^{-1}$. Schwarz and Rozen [Phys. Rev. Lett. {\bf 66}, 1898 (1991); Phys. Rev. B {\bf 44}, 7563 (1991)] observed a faster decay followed by a slower decay. More recently, Skrbek and collaborators [Phys. Rev. E {\bf 67}, 047302 (2003)] found an initial transient followed by the same classical $t^{-3/2}$ scaling observed in the decay of grid-generated turbulence. We present a simple theoretical model which, we argue, contains the essential physical ingredients, and accounts for these apparently contradictory results.

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Michele Sciacca, Yuri A. Sergeev, Carlo F. Barenghi, Ladik Skrbek. 2010-08-25. The saturation of decaying counterflow turbulence in helium II. https://doi.org/10.1103/physrevb.82.134531

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