### Abstract

We use data from well-resolved direct numerical simulations at Taylor-scale Reynolds numbers from 140 to 1000 to study the statistics of energy dissipation rate and enstrophy density (i.e. the square of local vorticity). Despite substantial variability in each of these variables, their extreme events not only scale in a similar manner but also progressively tend to occur spatially together as the Reynolds number increases. Though they possess non-Gaussian tails of enormous amplitudes, ratios of some characteristic properties can be closely linked to those of isotropic Gaussian random fields. We present results also on statistics of the pressure Laplacian and conditional mean pressure given both dissipation and enstrophy. At low Reynolds number intense negative pressure fluctuations are preferentially associated with rotation-dominated regions but at high Reynolds number both high dissipation and high enstrophy have similar effects.

Original language | English (US) |
---|---|

Pages (from-to) | 5-15 |

Number of pages | 11 |

Journal | Journal of Fluid Mechanics |

Volume | 700 |

DOIs | |

State | Published - Jun 10 2012 |

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### Keywords

- homogeneous turbulence
- intermittency
- turbulence simulation

### ASJC Scopus subject areas

- Mechanical Engineering
- Mechanics of Materials
- Condensed Matter Physics

### Cite this

*Journal of Fluid Mechanics*,

*700*, 5-15. https://doi.org/10.1017/jfm.2012.5

**Dissipation, enstrophy and pressure statistics in turbulence simulations at high Reynolds numbers.** / Yeung, P. K.; Donzis, D. A.; Sreenivasan, K. R.

Research output: Contribution to journal › Article

*Journal of Fluid Mechanics*, vol. 700, pp. 5-15. https://doi.org/10.1017/jfm.2012.5

}

TY - JOUR

T1 - Dissipation, enstrophy and pressure statistics in turbulence simulations at high Reynolds numbers

AU - Yeung, P. K.

AU - Donzis, D. A.

AU - Sreenivasan, K. R.

PY - 2012/6/10

Y1 - 2012/6/10

N2 - We use data from well-resolved direct numerical simulations at Taylor-scale Reynolds numbers from 140 to 1000 to study the statistics of energy dissipation rate and enstrophy density (i.e. the square of local vorticity). Despite substantial variability in each of these variables, their extreme events not only scale in a similar manner but also progressively tend to occur spatially together as the Reynolds number increases. Though they possess non-Gaussian tails of enormous amplitudes, ratios of some characteristic properties can be closely linked to those of isotropic Gaussian random fields. We present results also on statistics of the pressure Laplacian and conditional mean pressure given both dissipation and enstrophy. At low Reynolds number intense negative pressure fluctuations are preferentially associated with rotation-dominated regions but at high Reynolds number both high dissipation and high enstrophy have similar effects.

AB - We use data from well-resolved direct numerical simulations at Taylor-scale Reynolds numbers from 140 to 1000 to study the statistics of energy dissipation rate and enstrophy density (i.e. the square of local vorticity). Despite substantial variability in each of these variables, their extreme events not only scale in a similar manner but also progressively tend to occur spatially together as the Reynolds number increases. Though they possess non-Gaussian tails of enormous amplitudes, ratios of some characteristic properties can be closely linked to those of isotropic Gaussian random fields. We present results also on statistics of the pressure Laplacian and conditional mean pressure given both dissipation and enstrophy. At low Reynolds number intense negative pressure fluctuations are preferentially associated with rotation-dominated regions but at high Reynolds number both high dissipation and high enstrophy have similar effects.

KW - homogeneous turbulence

KW - intermittency

KW - turbulence simulation

UR - http://www.scopus.com/inward/record.url?scp=84864152612&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84864152612&partnerID=8YFLogxK

U2 - 10.1017/jfm.2012.5

DO - 10.1017/jfm.2012.5

M3 - Article

VL - 700

SP - 5

EP - 15

JO - Journal of Fluid Mechanics

JF - Journal of Fluid Mechanics

SN - 0022-1120

ER -