Spectral Modeling of Hydrodynamic and Magnetohydrodynamic Turbulent Flows

I will present a dynamical spectral Large Eddy Simulation (LES) model for the incompressible Navier-Stokes and magnetohydrodynamic equations based on the Eddy Damped Quasi Normal Markovian (EDQNM) equations. This model extends classical Large Eddy Simulations for the Navier-Stokes equations to incorporate general (non Kolmorovian) spectra as well as eddy noise. A new eddy-damping time is also derived for the EDQNM equations and added to the LES model. Effects of this enhancement will be discussed.