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Some results on the Navier-Stokes equations in connection with the statistical theory of stationary turbulence

Ricardo M. S. Rosa (2002)

Applications of Mathematics

Some rigorous results connected with the conventional statistical theory of turbulence in both the two- and three-dimensional cases are discussed. Such results are based on the concept of stationary statistical solution, related to the notion of ensemble average for turbulence in statistical equilibrium, and concern, in particular, the mean kinetic energy and enstrophy fluxes and their corresponding cascades. Some of the results are developed here in the case of nonsmooth boundaries and a less regular...

Sur le temps de vie de la turbulence bidimensionnelle

Thierry Gallay, Luis Miguel Rodrigues (2008)

Annales de la faculté des sciences de Toulouse Mathématiques

On sait que toutes les solutions de l’équation de Navier-Stokes dans R 2 dont le tourbillon est intégrable convergent lorsque t vers un écoulement autosimilaire appelé tourbillon d’Oseen. Dans cet article, nous donnons une estimation du temps nécessaire à la solution pour atteindre un voisinage du tourbillon d’Oseen à partir d’une donnée initiale arbitraire, mais bien localisée en espace. Nous obtenons ainsi une borne supérieure sur le temps de vie de la turbulence bidimensionnelle libre, en fonction...

Vorticity dynamics and turbulence models for large-Eddy simulations

Georges-Henri Cottet, Delia Jiroveanu, Bertrand Michaux (2003)

ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique

We consider in this paper the problem of finding appropriate models for Large Eddy Simulations of turbulent incompressible flows from a mathematical point of view. The Smagorinsky model is analyzed and the vorticity formulation of the Navier–Stokes equations is used to explore more efficient subgrid-scale models as minimal regularizations of these equations. Two classes of variants of the Smagorinsky model emerge from this approach: a model based on anisotropic turbulent viscosity and a selective...

Vorticity dynamics and turbulence models for Large-Eddy Simulations

Georges-Henri Cottet, Delia Jiroveanu, Bertrand Michaux (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

We consider in this paper the problem of finding appropriate models for Large Eddy Simulations of turbulent incompressible flows from a mathematical point of view. The Smagorinsky model is analyzed and the vorticity formulation of the Navier–Stokes equations is used to explore more efficient subgrid-scale models as minimal regularizations of these equations. Two classes of variants of the Smagorinsky model emerge from this approach: a model based on anisotropic turbulent viscosity and...

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