A new spectral model for shear-driven homogeneous anisotropic turbulent flows etc15 Tracking Number 201Presentation: Session: Atmospheric turbulence 2 Room: Room C Session start: 15:00 Tue 25 Aug 2015 Vincent Mons vincent.mons@sfr.fr Affifliation: Institut Jean le Rond d'Alembert, Sorbonne Univ, UPMC Univ Paris 06 and CNRS, UMR 7190, Paris, France Claude Cambon claude.cambon@ec-lyon.fr Affifliation: Laboratoire de Mécanique des Fluides et d’Acoustique, Université de Lyon, École Centrale de Lyon and CNRS, UMR 5509, Écully, France Pierre Sagaut pierre.sagaut@univ-amu.fr Affifliation: M2P2, Aix Marseille Université, École Centrale Marseille and CNRS, UMR 7340, Marseille, France Topics: - Atmospheric turbulence, - Geophysical and astrophysical turbulence, - Instability and transition, - Jets and wakes Abstract: A new system of governing equations for spherically-averaged descriptors, which allows to calculate incompressible homogeneous turbulent flows, is derived in the present study. Remarkable features of this model are that it makes a distinction between directional and polarization anisotropies, which are treated separately, and that no heuristic tuning of arbitrary constants is required. Spherical averaging allows to obtain a model for anisotropic turbulence which is as versatile as the classical Eddy-Damped Quasi-Normal Markovian (EDQNM) model for isotropic turbulence, i.e. this model can calculate anisotropic turbulent flows at both very high and low Reynolds numbers, with good resolution of both large and small scales and over very long evolution times. The present model is particulary suited for the study of shear-driven turbulent flows and their return to isotropy. |