REVERSIBILITY IN THE 3D INERTIAL TURBULENT CASCADE

etc15 Tracking Number 403

The inviscid nature of the of the inertial range of the turbulent energy cascade suggests that it should be reversible, and that reverse cascade effects should remain in normal turbulence. Using a reversible LES model, we study some properties of the direct and reverse cascades in isotropic turbulence. The reverse cascade is fairly stable and resilient to perturbations. The study of the Lyapunov exponents and eigenvectors of both cascades allows us to compute a ’viscous’ limit below which the system is enslaved to larger scales, and to characterize the most unstable solutions of the forward cascade. They appear to correspond to stretched vortices.