Extreme events in computational turbulence

P. K. Yeung, X. M. Zhai, Katepalli R. Sreenivasan

Research output: Contribution to journalArticle

Abstract

We have performed direct numerical simulations of homogeneous and isotropic turbulence in a periodic box with 8,1923 grid points. These are the largest simulations performed, to date, aimed at improving our understanding of turbulence small-scale structure. We present some basic statistical results and focus on "extreme" events (whose magnitudes are several tens of thousands the mean value). The structure of these extreme events is quite different from that of moderately large events (of the order of 10 times the mean value). In particular, intense vorticity occurs primarily in the form of tubes for moderately large events whereas it is much more "chunky" for extreme events (though probably overlaid on the traditional vortex tubes). We track the temporal evolution of extreme events and find that they are generally shortlived. Extreme magnitudes of energy dissipation rate and enstrophy occur simultaneously in space and remain nearly colocated during their evolution.

Original languageEnglish (US)
Pages (from-to)12633-12638
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Volume112
Issue number41
DOIs
StatePublished - Oct 13 2015

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turbulence
vorticity
vortex tubes
homogeneous turbulence
isotropic turbulence
direct numerical simulation
boxes
energy dissipation
grids
tubes
simulation

Keywords

  • Extreme events
  • Fluid dynamics
  • Intermittency
  • Petascale computing
  • Turbulence

ASJC Scopus subject areas

  • General

Cite this

Extreme events in computational turbulence. / Yeung, P. K.; Zhai, X. M.; Sreenivasan, Katepalli R.

In: Proceedings of the National Academy of Sciences of the United States of America, Vol. 112, No. 41, 13.10.2015, p. 12633-12638.

Research output: Contribution to journalArticle

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