The transport equation of subgrid scale (SGS) kinetic energy, KSGS, is used for the large-eddy simulation (LES), considering its possible consistency with dynamic procedure. The smallest scale portion in computationally resolved turbulence, which is estimated in the dynamic model, has closer relationship with largest scale in SGS. Therefore the dynamically determined parameter is more suitable for describing the energy transfer between resolved and SGS turbulence, rather than the energy dissipation through the SGS eddy-viscosity in the filtered equation of motion. Such an energy transfer is represented by the production term in the transport equation of KSGS in our model. Computational examination has been conducted for fully developed turbulent flow in a plane channel. Agreement with DNS database was fine and it was improved by refining the grid.

The transport equation of subgrid scale (SGS) kinetic energy, KSGS, is used for the large-eddy simulation (LES), considering its consistency with dynamic procedure. The dynamically determined parameter is suitable for describing the energy transfer from resolved turbulence to SGS portion. Thus the procedure is applied to the production term in the transport equation of KSGS, while the eddy viscosity in the filtered equation of motion is determined indirectly through KSGS. The statistically derived model for KSGS equation is adopted for the basis of our improvement. Computational examination has been conducted for fully developed turbulent flow in a plane channel. Agreement with DNS database was satisfactory. Moreover, in a channel on solid body rotation, our model reasonably reproduced the decay of SGS turbulence in the vicinity of the suction side.

No abstract

No abstract

No abstract