Non-equilibrium thermodynamics analysis of rotating counterflow superfluid turbulence

In two previous papers, two evolution equations for the vortex line density L, proposed by Vinen, were generalized to rotating superfluid turbulence and compared with each other. Here, the already generalized alternative Vinen equation is extended to the case in which counterflow and rotation are not collinear. Then, the obtained equation is considered from the viewpoint of non-equilibrium thermodynamics. According to this formalism, the compatibility between the evolution equation for L and the one for the velocity of the superfluid component is studied. The compatibility condition requires the presence of a new term dependent on the anisotropy of the tangle, which indicates how the friction force depends on the rotation rate.