Titre :

Autocorrelation function of velocity increments time series in fully developed turbulence

Auteur(s) :

Huang, Yongxiang [Auteur]
Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 [LOG]
Schmitt, François G [Auteur]
Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 [LOG]
Lu, Zhiming [Auteur]
Liu, Yulu [Auteur]

Titre de la revue :

EPL - Europhysics Letters

Pagination :

40010

Éditeur :

European Physical Society / EDP Sciences / Società Italiana di Fisica / IOP Publishing

Date de publication :

2009-05

ISSN :

0295-5075

Mot(s)-clé(s) en anglais :

Time series analysis
Stochastic analysis
Isotropic turbulence
homogeneous turbulence

Discipline(s) HAL :

Physique [physics]/Physique [physics]/Analyse de données, Statistiques et Probabilités [physics.data-an]
Physique [physics]/Mécanique [physics]/Mécanique des fluides [physics.class-ph]
Sciences de l'ingénieur [physics]/Mécanique [physics.med-ph]/Mécanique des fluides [physics.class-ph]
Physique [physics]/Physique [physics]/Dynamique des Fluides [physics.flu-dyn]

Résumé en anglais : [en]

In fully developed turbulence, the velocity field possesses long-range correlations, denoted by a scaling power spectrum or structure functions. Here we consider the autocorrelation function of velocity increment $\Delta ...
Lire la suite >In fully developed turbulence, the velocity field possesses long-range correlations, denoted by a scaling power spectrum or structure functions. Here we consider the autocorrelation function of velocity increment $\Delta u_{\ell}(t)$ at separation time $\ell$. Anselmet et al. [Anselmet et al. J. Fluid Mech. \textbf{140}, 63 (1984)] have found that the autocorrelation function of velocity increment has a minimum value, whose location is approximately equal to $\ell$. Taking statistical stationary assumption, we link the velocity increment and the autocorrelation function with the power spectrum of the original variable. We then propose an analytical model of the autocorrelation function. With this model, we prove that the location of the minimum autocorrelation function is exactly equal to the separation time $\ell$ when the scaling of the power spectrum of the original variable belongs to the range $0<\beta<2$. This model also suggests a power law expression for the minimum autocorrelation. Considering the cumulative function of the autocorrelation function, it is shown that the main contribution to the autocorrelation function comes from the large scale part. Finally we argue that the autocorrelation function is a better indicator of the inertial range than the second order structure function.Lire moins >

Langue :

Anglais

Comité de lecture :

Oui

Audience :

Internationale

Vulgarisation :

Non

Collections :

• Laboratoire d'Océanologie et de Géosciences (LOG) - UMR 8187

Source :

Harvested from HAL