### Abstract

It is shown that measurements of lower-dimensional projections of the scalar gradient in an isotropic conserved scalar field ζ(x,t) are sufficient to construct the probability density function (pdf) for the true scalar dissipation χ. With this general method, the true scalar dissipation pdf is obtained from the result reported recently for the approximate pdf based on |∇ζ|^{2} ≈ 3·(∂ζ/∂x)^{2}. Results show that (i) the pdf of the true scalar dissipation is virtually lognormal and (ii) the most probable value of χ increases and the rms fluctuations of χ decrease in comparison with their one-dimensional estimates.

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

Pages (from-to) | 1290-1292 |

Number of pages | 3 |

Journal | Physics of Fluids A |

Volume | 1 |

Issue number | 7 |

State | Published - 1989 |

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*,

*1*(7), 1290-1292.

**Lognormality of the scalar dissipation pdf in turbulent flows.** / Dahm, Werner; Buch, Kenneth A.

Research output: Contribution to journal › Article

*Physics of Fluids A*, vol. 1, no. 7, pp. 1290-1292.

}

TY - JOUR

T1 - Lognormality of the scalar dissipation pdf in turbulent flows

AU - Dahm, Werner

AU - Buch, Kenneth A.

PY - 1989

Y1 - 1989

N2 - It is shown that measurements of lower-dimensional projections of the scalar gradient in an isotropic conserved scalar field ζ(x,t) are sufficient to construct the probability density function (pdf) for the true scalar dissipation χ. With this general method, the true scalar dissipation pdf is obtained from the result reported recently for the approximate pdf based on |∇ζ|2 ≈ 3·(∂ζ/∂x)2. Results show that (i) the pdf of the true scalar dissipation is virtually lognormal and (ii) the most probable value of χ increases and the rms fluctuations of χ decrease in comparison with their one-dimensional estimates.

AB - It is shown that measurements of lower-dimensional projections of the scalar gradient in an isotropic conserved scalar field ζ(x,t) are sufficient to construct the probability density function (pdf) for the true scalar dissipation χ. With this general method, the true scalar dissipation pdf is obtained from the result reported recently for the approximate pdf based on |∇ζ|2 ≈ 3·(∂ζ/∂x)2. Results show that (i) the pdf of the true scalar dissipation is virtually lognormal and (ii) the most probable value of χ increases and the rms fluctuations of χ decrease in comparison with their one-dimensional estimates.

UR - http://www.scopus.com/inward/record.url?scp=0001758495&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0001758495&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0001758495

VL - 1

SP - 1290

EP - 1292

JO - Physics of fluids. A, Fluid dynamics

JF - Physics of fluids. A, Fluid dynamics

SN - 0899-8213

IS - 7

ER -