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Energy Spectra of Developed Turbulencein Helium Superfluids

Victor S. L'vov·Sergei V. Nazarenko·L. Skrbek
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Abstract

We suggest a "minimal model" for the 3D turbulent energy spectra in superfluids, based on their two-fluid description. We start from the Navier-Stokes equation for the normal fluid and from the coarse-grained hydrodynamic equation for the superfluid component (obtained from the Euler equation for the superfluid velocity after averaging over the vortex lines) and introduce a mutual friction coupling term, proportional to the counterflow velocity, the average superfluid vorticity and to the temperature dependent parameter $q=α/(1+α')$, where $α$ and $α'$ denote the dimensionless parameters characterizing the mutual friction between quantized vortices and the normal component of the liquid. We then derive the energy balance equations, taking into account the cross-velocity correlations. We obtain all asymptotical solutions for normal and superfluid energy spectra for limiting cases of small/big normal to superfluid density ratio and coupling. We discuss the applicability limits of our model to superfluid He II and to $^3$He-B and compare the model predictions with available experimental data.

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Victor S. L'vov, Sergei V. Nazarenko, L. Skrbek. 2006-06-01. Energy Spectra of Developed Turbulencein Helium Superfluids. https://doi.org/10.1007/s10909-006-9230-8

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