Superfluid Turbulence in the Kelvin Wave Cascade Regime

Abstract

Theoretical considerations are made of superfluid turbulence in the Kelvin wave cascade regime at low temperatures (T < 1K) and length scales of the order or smaller than the intervortical distance. The energy spectrum is shown to be in accord with the Kolmogorov scaling. The vortex line decay equation is shown to have an underlying Hamiltonian framework. Effects of spatial intermittency (exhibited in laboratory experiments) on superfluid turbulence are incorporated via the fractal nature of the vortex lines, for length scales of the order or smaller than the intervortical distance. The spatial intermittency effects are shown to enhance the vortex line density L, for a given value of intervortex spacing L, and to provide for a mechanism commensurate with the enhanced depolarization of vortex lines. The spatial intermittency is found to steepen the energy spectrum in qualitative agreement with laboratory experiments and to enhance vortex line decay.