Autocorrelation function of velocity ...
Type de document :
Article dans une revue scientifique
URL permanente :
Titre :
Autocorrelation function of velocity increments time series in fully developed turbulence
Auteur(s) :
Huang, Yongxiang [Auteur]
Schmitt, François G [Auteur]
Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 [LOG]
Lu, Z.M. [Auteur]
Liu, Yl [Auteur]
Schmitt, François G [Auteur]
Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 [LOG]
Lu, Z.M. [Auteur]
Liu, Yl [Auteur]
Titre de la revue :
EPL - Europhysics Letters
Pagination :
40010, 2009.
Éditeur :
European Physical Society/EDP Sciences/Società Italiana di Fisica/IOP Publishing
Date de publication :
2009
ISSN :
0295-5075
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 Δu ℓ (t) ...
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 Δu ℓ (t) at separation {time} ℓ . 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 ℓ . 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} ℓ when the scaling of the power spectrum of the original variable belongs to the range 0<β<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 functionLire moins >
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 Δu ℓ (t) at separation {time} ℓ . 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 ℓ . 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} ℓ when the scaling of the power spectrum of the original variable belongs to the range 0<β<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 functionLire moins >
Langue :
Anglais
Comité de lecture :
Oui
Audience :
Internationale
Vulgarisation :
Non
Source :
Date de dépôt :
2022-04-08T07:19:49Z