Hilbert statistics of vorticity scaling in two-dimensional turbulence

  title={Hilbert statistics of vorticity scaling in two-dimensional turbulence},
  author={H. S. Tan and Y. X. Huang and Jianping Meng},
  journal={Physics of Fluids},
In this paper, the scaling property of the inverse energy cascade and forward enstrophy cascade of the vorticity filed ω(x, y) in two-dimensional (2D) turbulence is analyzed. This is accomplished by applying a Hilbert-based technique, namely Hilbert-Huang transform, to a vorticity field obtained from a 81922 grid-points direct numerical simulation of the 2D turbulence with a forcing scale k f = 100 and an Ekman friction. The measured joint probability density function p(C, k) of mode C i (x) of… 

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