A Langevin equation for turbulent velocity increments - Archive ouverte HAL Access content directly
Journal Articles Physics of Fluids Year : 2001

A Langevin equation for turbulent velocity increments

Abstract

Recently, Friedrich and Peinke demonstrated empirically that a Fokker–Planck equation describes the scale dependence of probability distribution functions of longitudinal velocity increments vr in fully developed turbulent flows. Thanks to the analysis of an experimental velocity signal, the stochastic process vr is further investigated by examining the related Langevin equation. This process is found to be Markovian in scale because the turbulent velocity field is correlated over distances much larger than the correlation length r of its spatial derivative. A Gaussian approximation for the random force yields evolution equations for the structure functions ^vr n&. Analytic solutions are obtained, in agreement with experimental data for even-order moments when the scale r is larger than a few times r. The third-order moment ^vr 3& is found linear in r, as predicted by Kolmogorov’s four-fifths law.
Fichier principal
Vignette du fichier
Marcq_Naert_POF_2001.pdf (349.52 Ko) Télécharger le fichier
Origin : Publisher files allowed on an open archive
Loading...

Dates and versions

hal-01140942 , version 1 (11-04-2015)

Identifiers

Cite

Philippe Marcq, Antoine Naert. A Langevin equation for turbulent velocity increments. Physics of Fluids, 2001, 13 (9), pp.2590. ⟨10.1063/1.1386937⟩. ⟨hal-01140942⟩
89 View
343 Download

Altmetric

Share

Gmail Facebook X LinkedIn More