English

Richardson's pair diffusion and the stagnation point structure of turbulence

Fluid Dynamics 2009-11-07 v1 Atmospheric and Oceanic Physics

Abstract

DNS and laboratory experiments show that the spatial distribution of straining stagnation points in homogeneous isotropic 3D turbulence has a fractal structure with dimension D_s = 2. In Kinematic Simulations the time exponent gamma in Richardson's law and the fractal dimension D_s are related by gamma = 6/D_s. The Richardson constant is found to be an increasing function of the number of straining stagnation points in agreement with pair duffusion occuring in bursts when pairs meet such points in the flow.

Keywords

Cite

@article{arxiv.physics/0207108,
  title  = {Richardson's pair diffusion and the stagnation point structure of turbulence},
  author = {Javier Davila and Christos Vassilicos},
  journal= {arXiv preprint arXiv:physics/0207108},
  year   = {2009}
}

Comments

4 pages; Submitted to Phys. Rev. Lett