The interaction between vortex-density waves and high-frequency second sound in counterflow superfluid turbulence is examined, incorporating diffusive and elastic contributions of the vortex tangle. The analysis is based on a set of evolution equations for the energy density, the heat flux, the vortex line density, and the vortex flux, the latter being considered here as an independent variable, in contrast to previous works. The latter feature is crucial in the transition from diffusive to propagative behavior of vortex-density perturbations, which is necessary to interpret the details of high-frequency second sound. © 2007 Elsevier Ltd. All rights reserved.
- Liquid Helium II
- Non-equilibrium thermodynamics
- Second sound
- Superfluid turbulence
- Vortex waves