English

Distributed chaos and Rayleigh-Benard turbulence at very high Ra

Fluid Dynamics 2016-11-02 v1 Solar and Stellar Astrophysics Chaotic Dynamics

Abstract

It is shown, by the means of distributed chaos approach and using the experimental data, that at very large Rayleigh number Ra>1014Ra > 10^{14} and Prandtl number Pr1Pr \sim 1 the Rayleigh-B\'{e}nard turbulence can undergo a transition related to spontaneous breaking of the fundamental Lagrangian relabeling symmetry. Due to the Noether's theorem helicity plays central role in this process. After the transition the temperature spectrum has a stretched exponential form E(k)exp(k/kβ)βE (k) \propto \exp(-k/k_{\beta})^{\beta} with β=2/5\beta =2/5 both at the cell midplain and at the near-wall (low boundary) regions. There is a similarity between this phenomenon and the effects of polymer additives.

Keywords

Cite

@article{arxiv.1608.04657,
  title  = {Distributed chaos and Rayleigh-Benard turbulence at very high Ra},
  author = {A. Bershadskii},
  journal= {arXiv preprint arXiv:1608.04657},
  year   = {2016}
}