### Abstract

The Lagrangian and Eulerian frequency spectrum in isotropic turbulence is considered without a mean flow, concentrating on its second moment, the mean-square acceleration. The pressure and viscous contributions are reviewed and the scaling properties of the advective term 〈[(v·∇)v] ^{2}〉 are examined. Random sweeping from this term is shown to be dominant at large Reynolds numbers if the fluctuation spectrum of the kinetic energy v^{2}(x) scales as k ^{-5/3}. If on the other hand it satisfies the same Kolmogorov scaling as the pressure going as k ^{-7/3}, then the recent renormalization group prediction of no sweeping is recovered. This question is subject to direct experimental resolution. The experiments of Van Atta and Wyngaard [J. Fluid Mech. 72, 673 (1975)] strongly indicate that the spectrum of v^{2} goes as k ^{-5/3} at high Reynolds numbers, thereby supporting the sweeping hypothesis.

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

Pages (from-to) | 81-83 |

Number of pages | 3 |

Journal | Physics of Fluids A |

Volume | 2 |

Issue number | 1 |

State | Published - 1990 |

Externally published | Yes |

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### ASJC Scopus subject areas

- Condensed Matter Physics
- Physics and Astronomy(all)
- Mechanics of Materials
- Computational Mechanics
- Fluid Flow and Transfer Processes

### Cite this

*Physics of Fluids A*,

*2*(1), 81-83.

**Time correlations and random sweeping in isotropic turbulence.** / Nelkin, Mark; Tabor, Michael.

Research output: Contribution to journal › Article

*Physics of Fluids A*, vol. 2, no. 1, pp. 81-83.

}

TY - JOUR

T1 - Time correlations and random sweeping in isotropic turbulence

AU - Nelkin, Mark

AU - Tabor, Michael

PY - 1990

Y1 - 1990

N2 - The Lagrangian and Eulerian frequency spectrum in isotropic turbulence is considered without a mean flow, concentrating on its second moment, the mean-square acceleration. The pressure and viscous contributions are reviewed and the scaling properties of the advective term 〈[(v·∇)v] 2〉 are examined. Random sweeping from this term is shown to be dominant at large Reynolds numbers if the fluctuation spectrum of the kinetic energy v2(x) scales as k -5/3. If on the other hand it satisfies the same Kolmogorov scaling as the pressure going as k -7/3, then the recent renormalization group prediction of no sweeping is recovered. This question is subject to direct experimental resolution. The experiments of Van Atta and Wyngaard [J. Fluid Mech. 72, 673 (1975)] strongly indicate that the spectrum of v2 goes as k -5/3 at high Reynolds numbers, thereby supporting the sweeping hypothesis.

AB - The Lagrangian and Eulerian frequency spectrum in isotropic turbulence is considered without a mean flow, concentrating on its second moment, the mean-square acceleration. The pressure and viscous contributions are reviewed and the scaling properties of the advective term 〈[(v·∇)v] 2〉 are examined. Random sweeping from this term is shown to be dominant at large Reynolds numbers if the fluctuation spectrum of the kinetic energy v2(x) scales as k -5/3. If on the other hand it satisfies the same Kolmogorov scaling as the pressure going as k -7/3, then the recent renormalization group prediction of no sweeping is recovered. This question is subject to direct experimental resolution. The experiments of Van Atta and Wyngaard [J. Fluid Mech. 72, 673 (1975)] strongly indicate that the spectrum of v2 goes as k -5/3 at high Reynolds numbers, thereby supporting the sweeping hypothesis.

UR - http://www.scopus.com/inward/record.url?scp=0002995439&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0002995439&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0002995439

VL - 2

SP - 81

EP - 83

JO - Physics of fluids. A, Fluid dynamics

JF - Physics of fluids. A, Fluid dynamics

SN - 0899-8213

IS - 1

ER -