Longitudinal counterflow in turbulent liquid helium: velocity profile of the normal component

Abstract

In this paper, the velocity profile of the normal component in the stationary flow of turbulent superfluid helium inside a cylindrical channel is determined, making use of a one-fluid model with internal variables \ud derived from Extended Thermodynamics. In the hypothesis of null barycentric velocity of the fluid (the so-called counterflow situation) it is seen that, in the presence of a sufficiently high vortex length density, the velocity profile of the normal component becomes very flat in the central region of the channel.\ud Thus, a central flat profile of the normal fluid does not necessarily imply that the flow of the normal component is turbulent

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Thermodynamics of computation and linear stability limits of superfluid refrigeration of a model computing array

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Heat rectification in He II counterflow in radial geometries

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