Eddy-resolving ocean models suggest that the transport of Antarctic Circumpolar Current (ACC) may be insensitive to increasing wind. This insensitivity is due eddies flatten isopycnals and compensate for their wind-driven steepening. However, eddy-resolving do not accurately represent eddy dissipation processes occur at scales smaller than model resolution, including lee wave generation rough t...

In view of the application limits modified eddy dissipation model (MEDM) in simulations weakly turbulent flow, compressible and internal an improved (IEDM) is proposed. The IEDM uses dissociation reactions to obtain correct combustion temperature instead specific heat compensation used MEDM model. This extends flow simulation. simulation accuracy for by using accurate transport property maximum...

We examine the changes in kinetic energy dissipation of a turbulent channel flow caused by a spanwise magnetic field. The numerical study is based on our simulation data from [1] obtained by direct and large eddy simulations. We find that the Joule dissipation can exceed the viscous dissipation in the weakly dissipative bulk region, but remains comparatively small in the turbulence-generating n...

Discussed is the use of tctroons to obtain cstiinates of the Reynolds stresses, the rate of production of eddy kitictic energy through these stresses, thc coefficictit of eddy viscosity, and thc viscous dissipation within thc planetary boundary layer. At a n average height of about 3000 ft. (admittedly in thc upper portion of the boundary layer) the tetroons yield a mean value for the zonal Rey...

Parameterizations of the eddy-induced velocity that advects tracers in addition to the Eulerian mean flow are traditionally expressed as a downgradient Fickian diffusion of either isopycnal layer thickness or large-scale potential vorticity (PV). There is an ongoing debate on which of the two closures is better and how the spatial dependence of the eddy diffusivity should look like. To increase...

In recent years field experiments have been undertaken in the lower atmosphere to perform a priori tests of subgrid-scale (SGS)models for large-eddy simulations (LES). The experimental arrangements and data collected have facilitated studies of variables such as the filtered strain rate, SGS stress and dissipation, and the eddy viscosity coefficient. However, the experimental set-ups did not pe...

Explicit filtering has the effect of reducing numerical or aliasing errors near the grid scale in large eddy simulation (LES). We use a differential filter, namely the inverse Helmholtz operator, which is readily applied to unstructured meshes. The filter is invertible, which allows the sub-filter scale (SFS) stresses to be exactly reconstructed in terms of the filtered solution. Unlike eddy vi...

Submitted for the DFD08 Meeting of The American Physical Society On discretization errors and subgrid scale model implementations in Large Eddy Simulations BERNARD KNAEPEN, AXELLE VIRÉ, Université Libre de Bruxelles — We analyze the impact of discretization errors on the performance of the Smagorinsky model in Large Eddy Simulations (LES). To avoid difficulties related to solid boundaries, we f...