A new spectral closure theory for stably stratified turbulent flows is presented. It is based upon a quasi-Gaussian mapping, the use of the Langevin equation and an algorithm of successive small scales elimination. The new theory allows for a broad insight into the dynamics of stably stratified flows. It accounts for the flow anisotropy and provides expressions for vertical and horizontal eddy viscosities and diffusivities. A combined effect of turbulence and waves is considered. A dispersion relation for internal waves in the presence of turbulence is derived. The model is used to derive new RANS models. A new K-ɛ model and the results of its application to atmospheric boundary layers over ice will be presented.
|Title of host publication||American Physical Society, Division of Fluid Dynamics 56th Annual Meeting|
|State||Published - 1 Nov 2003|