A vortex-based subgrid stress model for large-eddy simulation

A vortex-based subgrid stress model for large-eddy simulation

A class of subgrid stress ~SGS! models for large-eddy simulation ~LES! is presented based on the idea of structure-based Reynolds-stress closure. The subgrid structure of the turbulence is assumed to consist of stretched vortices whose orientations are determined by the resolved velocity field. An equation which relates the subgrid stress to the structure orientation and the subgrid kinetic ene...

A physical-space version of the stretched-vortex subgrid-stress model for large-eddy simulation

A physical-space version of the stretched-vortex subgrid-stress model is presented and applied to large-eddy simulations of incompressible flows. This version estimates the subgrid-kinetic energy required for evaluation of the subgrid-stress tensor using local second-order structure-function information of the resolved velocity field at separations of order the local cell size. A relation betwe...

A Tensor-diffusivity Subgrid Model for Large-Eddy Simulation

Subgrid-scale models for large-eddy simulation that are based on exact series expansions for ltered products are considered. In particular, if the rst two terms are retained, the result is a di usive subgrid term with a tensor di usivity. This tensor is proportional to the rate-of-strain tensor of the large-scale velocity eld. This leads to negative di usion in the stretching directions. Implic...

A dynamic global-coefficient subgrid-scale eddy-viscosity model for large-eddy simulation in complex geometries

A new subgrid eddy-viscosity model for large-eddy simulation of anisotropic turbulence

A new subgrid eddy-viscosity model is proposed in this paper. Full details of the derivation of the model are given with the assumption of homogeneous turbulence. The formulation of the model is based on the dynamic equation of the structure function of resolved scale turbulence. By means of the local volume average, the effect of the anisotropy is taken into account in the generalized Kolmogor...