Non-equilibrium steady state of the superfluid mixtures of helium isotopes at classical temperatures

Abstract

The size effect in the gas of impuritons of the superfluid mixtures of helium isotopes is investigated by taking into consideration the contribution of thermal excitations. The solution is obtained for the set of kinetic equations describing a non-equilibrium state of the phonon-impuriton system of a superfluid mixture situated in the volume filled with the macroparticles. It allows to find the condition describing a steady, thermodynamically non-equilibrium state of $^3{He}-^4{He}$ mixture in confined geometry. The Knudsen effect in the gas of impuritons of a superfluid mixture is investigated by taking into account the contribution of phonons. A model for the collision operator has been proposed to analyze the exact results in the context of the concrete physical situations. An experiment for the investigation of the Knudsen effect in a superfluid mixture of helium isotopes is proposed.