### Abstract

Original language | Undefined |
---|---|

Pages (from-to) | 347-352 |

Journal | Europhysics letters |

Volume | 27 |

Issue number | 5 |

DOIs | |

Publication status | Published - 1994 |

### Keywords

- IR-50332

### Cite this

*Europhysics letters*,

*27*(5), 347-352. https://doi.org/10.1209/0295-5075/27/5/003

}

*Europhysics letters*, vol. 27, no. 5, pp. 347-352. https://doi.org/10.1209/0295-5075/27/5/003

**Fractal dimension crossovers in turbulent passive scalar signals.** / Grossmann, Siegfried; Lohse, Detlef.

Research output: Contribution to journal › Article › Academic

TY - JOUR

T1 - Fractal dimension crossovers in turbulent passive scalar signals

AU - Grossmann, Siegfried

AU - Lohse, Detlef

PY - 1994

Y1 - 1994

N2 - The fractal dimension δg(1) of turbulent passive scalar signals is calculated from the fluid dynamical equation. δg(1) depends on the scale. For small Prandtl (or Schmidt) number Pr < 10-2 one gets two ranges, δg(1) = 1 for small-scale r and δg(1) = 5/3 for large r, both as expected. But for large Pr > 1 one gets a third, intermediate range in which the signal is extremely wrinkled and has δg(1) = 2. In that range the passive scalar structure function Dθ(r) has a plateau. We calculate the Pr-dependence of the crossovers. The plateau regime can be observed in a numerical solution of the fluid dynamical equation, employing a reduced wave vector set approximation introduced by us recently.

AB - The fractal dimension δg(1) of turbulent passive scalar signals is calculated from the fluid dynamical equation. δg(1) depends on the scale. For small Prandtl (or Schmidt) number Pr < 10-2 one gets two ranges, δg(1) = 1 for small-scale r and δg(1) = 5/3 for large r, both as expected. But for large Pr > 1 one gets a third, intermediate range in which the signal is extremely wrinkled and has δg(1) = 2. In that range the passive scalar structure function Dθ(r) has a plateau. We calculate the Pr-dependence of the crossovers. The plateau regime can be observed in a numerical solution of the fluid dynamical equation, employing a reduced wave vector set approximation introduced by us recently.

KW - IR-50332

U2 - 10.1209/0295-5075/27/5/003

DO - 10.1209/0295-5075/27/5/003

M3 - Article

VL - 27

SP - 347

EP - 352

JO - Europhysics letters

JF - Europhysics letters

SN - 0295-5075

IS - 5

ER -