Double cascade turbulence and Richardson dispersion in a horizontal fluid flow induced by Faraday waves

Phys Rev Lett. 2011 Aug 12;107(7):074502. doi: 10.1103/PhysRevLett.107.074502. Epub 2011 Aug 12.

Abstract

We report the experimental observation of Richardson dispersion and a double cascade in a thin horizontal fluid flow induced by Faraday waves. The energy spectra and the mean spectral energy flux obtained from particle image velocimetry data suggest an inverse energy cascade with Kolmogorov type scaling E(k) ∝ k(γ), γ ≈ -5/3 and an E(k) ∝ k(γ), γ ≈ -3 enstrophy cascade. Particle transport is studied analyzing absolute and relative dispersion as well as the finite size Lyapunov exponent (FSLE) via the direct tracking of real particles and numerical advection of virtual particles. Richardson dispersion with <ΔR(2)(t)> ∝ t(3) is observed and is also reflected in the slopes of the FSLE (Λ ∝ ΔR(-2/3)) for virtual and real particles.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Hydrodynamics*
  • Motion
  • Spectrum Analysis