Laboratoire de Mécanique des Fluides et d'Acoustique - UMR 5509

LMFA - UMR 5509
Laboratoire de Mécanique des Fluides et d’Acoustique
Lyon
France


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Accueil > Équipes > Turbulence & Instabilités > Thématiques > Turbulence et modélisation

Turbulence stratifiée et/ou en rotation

Turbulence stratifiée et/ou en rotation

La turbulence en rotation —par exemple dans les turbomachines, dans les atmosphères planétaires, ou dans l’océan avec la force de Coriolis— a une dynamique très particulière. Dans le contexte homogène, elle développe des structures allongées verticalement sous forme de colonnes dites de Taylor. Cette structure anisotrope multi-échelles est analysée au moyen de statistiques eulériennes, notamment les statistiques d’alignement, et lagrangiennes en quatre points par des tétrades. Nous avons pu mettre en évidence le rôle des échelles de Hopfinger-Zeman dans l’anisotropie des petites échelles ainsi que des mécanismes d’anti-alignement des structures avec l’axe de rotation.

La turbulence stratifiée, caractérisée par des variations verticales de densité moyenne dans un champ turbulent homogène en présence d’une accélération (gravité notamment), se comporte très différemment selon qu’il s’agit d’une stratification stable ou instable.
Le premier cas conduit à des ondes internes de gravité, souvent associées à des structures horizontales (feuillets), alors que dans le second se développent des bouffées allongées verticalement, comme dans l’instabilité ``explosive’’de Rayleigh-Taylor.
Les deux cas sont modélisés par des DNS, elles-même comparées aux modèles de type EDQNM. 
Le contexte instable est pertinent pour obtenir des modèles prédictifs à très grand nombre de Reynolds, en lien avec la fusion par confinement inertiel ou en astrophysique.

Personnels principalement impliqués : A. Naso, A. Delache, F. Godeferd, C. Cambon ;
Collaborations : CEA/DAM, Univ. de Tunis, LUTH (observatoire de Paris).


Publications associées :

Linking dissipation, anisotropy, and intermittency in rotating stratified turbulence at the threshold of linear shear instabilities

Article dans Phys. Fluids (2019)

Linking dissipation, anisotropy, and intermittency in rotating stratified turbulence at the threshold of linear shear instabilities

Annick Pouquet, Duane Rosenberg & Raffaele Marino

Analyzing a large database of high-resolution three-dimensional direct numerical simulations of decaying rotating stratified flows, we show that anomalous mixing and dissipation, marked (...)

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Multiscale analysis of the structure of homogeneous rotating turbulence

Article dans Phys. Rev. Fluids (2019)

Multiscale analysis of the structure of homogeneous rotating turbulence

Aurore Naso

The structure of homogeneous rotating turbulence at moderate Reynolds number is investigated by analyzing the instantaneous statistics of the scale-dependent velocity gradient tensor perceived by (...)

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The size and lifetime of organised eddies in a non-solid-body rotating turbulence experiment

Article dans Eur. J. Mech. B-Fluids (2019)

The size and lifetime of organised eddies in a non-solid-body rotating turbulence experiment

Lian Gan & Andrea Maffioli

This paper follows our previous study of forced non-solid-body rotating turbulence and summarises results on the eddy size and lifetime in the same flow. The experiment is conducted in a (...)

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Small-scale anisotropy induced by spectral forcing and by rotation in non-helical and helical turbulence

Article dans J. Turbul. (2018)

Small-scale anisotropy induced by spectral forcing and by rotation in non-helical and helical turbulence

Donato Vallefuoco, Aurore Naso, Fabien S. Godeferd

We study the effect of large-scale spectral forcing on the scale-dependent anisotropy of the velocity field in direct numerical simulations of homogeneous turbulence. ABC-type forcing and helical (...)

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Spectral energy scaling in precessing turbulence

Article dans Phys. Rev. E (2018)

Spectral energy scaling in precessing turbulence

A. Khlifi, A. Salhi, S. Nasraoui, F. Godeferd & C. Cambon

We study precessing turbulence, which appears in several geophysical and astrophysical systems, by direct numerical simulations of homogeneous turbulence where precessional instability is (...)

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A statistical mechanics approach to mixing in stratified fluids

Article dans J. Fluid Mech. (2017)

A statistical mechanics approach to mixing in stratified fluids

A. Venaille, L. Gostiaux and J. Sommeria

Predicting how much mixing occurs when a given amount of energy is injected into a Boussinesq fluid is a long-standing problem in stratified turbulence. The huge number of degrees of freedom (...)

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Waves and vortices in the inverse cascade regime of stratified turbulence with or without rotation

Article dans J. Fluid Mech. (2016)

Waves and vortices in the inverse cascade regime of stratified turbulence with or without rotation

Corentin Herbert, Raffaele Marino, Duane Rosenberg & Annick Pouquet

We study the partition of energy between waves and vortices in stratified turbulence, with or without rotation, for a variety of parameters, focusing on the behaviour of the waves and vortices in (...)

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Dynamics and structure of unstably stratified homogeneous turbulence

Article dans J. Turbul. (2016)

Dynamics and structure of unstably stratified homogeneous turbulence

Benoît-Joseph Gréa, Alan Burlot, Fabien S. Godeferd, Jérôme Griffond, Olivier Soulard, Claude Cambon

We characterise the properties of unstably stratified homogeneous turbulence by means of high-resolution direct numerical simulations and a two-point statistical spectral model based on a (...)

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Structure of sheared and rotating turbulence : Multiscale statistics of Lagrangian and Eulerian accelerations and passive scalar dynamics

Article dans Phys. Rev. E (2016)

Structure of sheared and rotating turbulence : Multiscale statistics of Lagrangian and Eulerian accelerations and passive scalar dynamics

Frank G. Jacobitz, Kai Schneider, Wouter J.T. Bos & Marie Farge

The acceleration statistics of sheared and rotating homogeneous turbulence are studied using direct numerical simulation results. The statistical properties of Lagrangian and Eulerian (...)

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A spectral model for homogeneous shear-driven anisotropic turbulence in terms of spherically averaged descriptors

Article dans J. Fluid Mech. (2016)

A spectral model for homogeneous shear-driven anisotropic turbulence in terms of spherically averaged descriptors

Vincent Mons, Claude Cambon & Pierre Sagaut

A nonlinear spectral model in terms of spherically averaged descriptors is derived for the prediction of homogeneous turbulence dynamics in the presence of arbitrary mean-velocity gradients. The (...)

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Large Reynolds number self-similar states of unstably stratified homogeneous turbulence

Article dans Phys. Fluids (2015)

Large Reynolds number self-similar states of unstably stratified homogeneous turbulence

A. Burlot, B.-J. Gréa, F. S. Godeferd, C. Cambon & O. Soulard

We study the influence of the large scale energy distribution on the long term dynamics of unstably stratified homogeneous turbulence at high Reynolds number $Re = 10^6$, using a statistical (...)

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Cyclone-anticyclone asymmetry and alignment statistics in homogeneous rotating turbulence

Article dans Phys. Fluids (2015)

Cyclone-anticyclone asymmetry and alignment statistics in homogeneous rotating turbulence

Aurore Naso

The cyclone-anticyclone asymmetry occurring in rotating turbulence is investigated through the analysis of the alignment statistics between vorticity and the rotation vector. The advantage of (...)

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Structure and dynamics of rotating turbulence : a review of recent experimental and numerical results

Article dans Appl. Mech. Rev. (2015)

Structure and dynamics of rotating turbulence : a review of recent experimental and numerical results

Fabien Godeferd & Frédéric Moisy

Rotating turbulence is a fundamental phenomenon appearing in several geophysical and industrial applications. Its study benefited from major advances in the recent years, but also raised new (...)

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Spectral modelling of high Reynolds number unstably stratified homogeneous turbulence

Article dans J. Fluid Mech. (2015)

Spectral modelling of high Reynolds number unstably stratified homogeneous turbulence

A. Burlot, B.-J. Gréa, F. S. Godeferd, C. Cambon & J. Griffond

We study unconfined homogeneous turbulence with a destabilizing background density gradient in the Boussinesq approximation. Starting from initial isotropic turbulence, the buoyancy force induces (...)

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Strain and Stratification Effects on the Rapid Acceleration of a Turbulent Mixing Zone

Article dans J. Fluids Eng. (2014)

Strain and Stratification Effects on the Rapid Acceleration of a Turbulent Mixing Zone

Benoît-Joseph Gréa, Jérôme Griffond & Fabien Godeferd

We consider the problem of a turbulent mixing zone (TMZ), initially submitted to coupled effects of axisymmetric strain and stratification, then subsequently accelerated. The TMZ grows in the (...)

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Cross-helicity in Rotating Homogeneous Shear-Stratified Turbulence

Article dans Phys. Rev. letters (2014)

Cross-helicity in Rotating Homogeneous Shear-Stratified Turbulence

A. B. Pieri, F. S. Godeferd, C. Cambon, B. Dubrulle & S. Thalabard

We consider homogeneous shear-stratified turbulence in a rotating frame, that exhibits complex nonlinear dynamics. Since the analysis of relative orientation between coupled fluctuating fields (...)

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Scale by scale anisotropy in freely decaying rotating turbulence

Article dans Phys. Fluids (2014)

Scale by scale anisotropy in freely decaying rotating turbulence

Alexandre Delache, Claude Cambon & Fabien Godeferd

We analyse the anisotropy present at different scales in rotating homogeneous turbulence. The Zeman wavenumber $k_\Omega$ [O. Zeman, “A note on the spectra and decay of rotating homogeneous (...)

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Nonlinear dynamics and anisotropic structure of rotating sheared turbulence

Article dans Phys. Rev. E (2014)

Nonlinear dynamics and anisotropic structure of rotating sheared turbulence

A. Salhi, F. G. Jacobitz, K. Schneider & C. Cambon

Homogeneous turbulence in rotating shear flows is studied by means of pseudospectral direct numerical simulation and analytical spectral linear theory (SLT). The ratio of the Coriolis parameter (...)

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