Mutual-friction induced instability of normal-fluid vortex tubes in superfluid helium-4

Kivotides, Demosthenes (2018) Mutual-friction induced instability of normal-fluid vortex tubes in superfluid helium-4. Physics Letters A, 382 (22). pp. 1481-1485. ISSN 0375-9601

[img]
Preview
Text (Kivotides-PLA-2018-Mutual-friction-induced-instability-of-normal-fluid-vortex)
Kivotides_PLA_2018_Mutual_friction_induced_instability_of_normal_fluid_vortex.pdf
Accepted Author Manuscript
License: Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 logo

Download (1MB)| Preview

    Abstract

    It is shown that, as a result of its interactions with superfluid vorticity, a normal-fluid vortex tube in helium-4 becomes unstable and disintegrates. The superfluid vorticity acquires only a small (few percents of normal-fluid tube strength) polarization, whilst expanding in a front-like manner in the intervortex space of the normal-fluid, forming a dense, unstructured tangle in the process. The accompanied energy spectra scalings offer a structural explanation of analogous scalings in fully developed finite-temperature superfluid turbulence. A macroscopic mutual-friction model incorporating these findings is proposed.