Vortex-density fluctuations, energy spectra, and vortical regions in superfluid turbulence.

  title={Vortex-density fluctuations, energy spectra, and vortical regions in superfluid turbulence.},
  author={Andrew W. Baggaley and Jason Laurie and C F Barenghi},
  journal={Physical review letters},
  volume={109 20},
Measurements of the energy spectrum and of the vortex-density fluctuation spectrum in superfluid turbulence seem to contradict each other. Using a numerical model, we show that at each instance of time the total vortex line density can be decomposed into two parts: one formed by metastable bundles of coherent vortices, and one in which the vortices are randomly oriented. We show that the former is responsible for the observed Kolmogorov energy spectrum, and the latter for the spectrum of the… 

Orthogonal and antiparallel vortex tubes and energy cascades in quantum turbulence

We investigate the dynamics of energy cascades in quantum turbulence by directly observing the vorticity distributions in numerical simulations of the Gross-Pitaevskii equation. By Fourier filtering

Local and nonlocal dynamics in superfluid turbulence

Turbulence in superfluid helium~II is a tangle of quantized vortex lines which interact via the classical Biot-Savart law. We show that vortex tangles with the same vortex line density will have

Velocity spectra of quantum turbulence: experiments, numerics and models

Superfluid Turbulence is unusual and presents a challenge to fluid dynamicists because it consists of two coupled, inter penetrating turbulent fluids: the first is inviscid with quantised vorticity,

Experimental, numerical, and analytical velocity spectra in turbulent quantum fluid

Experimental, numerical, and theoretical results are presented that explain the similarities of the observed spectra of the superfluid turbulent velocity at sufficiently large length scales and illustrate the limits of the present understanding of superfluid turbulence at smaller scales.

Signatures of coherent vortex structures in a disordered two-dimensional quantum fluid

The emergence of coherent rotating structures is a phenomenon characteristic of both classical and quantum two-dimensional (2D) turbulence. In this work we show theoretically that the coherent vortex

Mesoscale helicity distinguishes Vinen from Kolmogorov turbulence in helium-II

Experiments and numerical simulations show that quantum turbulence exists in two distinct limiting regimes: Kolmogorov turbulence (which shares with classical turbulence the important property of a

Vorticity Locking and Pressure Dynamics in Finite-Temperature Superfluid Turbulence

We present a numerical study of finite-temperature superfluid turbulence using the vortex filament model for superfluid helium. We examine the phenomenon of vorticity locking between the normal and

Non-classical Velocity Statistics in Counterflow Quantum Turbulence

In this work we analyse the statistical distribution of turbulent superfluid velocity components in a He II counterflow channel, via two-dimensional numerical simulations presented in past studies.

Quantum Ferrofluid Turbulence.

The authors' simulations reveal that the dipolar interactions drive the emergence of polarized turbulence and density corrugations, which poses exciting prospects for realizing stratified quantum turbulence and new levels of generating and controlling turbulence using magnetic fields.

Vortex clustering, polarisation and circulation intermittency in classical and quantum turbulence

This work links the spatial distribution of vortices in quantum turbulence to the coarse-grained energy dissipation in classical turbulence, enabling the application of existent models of classical turbulence intermittency to the quantum case.