The original (delayed) detached-eddy simulation ((D)DES), a widely used and efficient hybrid turbulence method, is confronted with some flaws containing grid-induced separation (GIS), log-layer mismatch (LLM), slow RANS-LES transition. A novel model, namely production-limited eddy (PLES), depleting the production through introducing subarid-scale viscosity proposed. data of zero-pressure gradie...

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...

Two-parametric eddy viscosity (TPEV) and other spectral characteristics of two-dimensional (2D) turbulence in the energy transfer sub-range are calculated from direct numerical simulation (DNS) with 5122 resolution. The DNS-based TPEV is compared with those calculated from the test field model (TFM) and from the renormalization group (RG) theory. Very good agree-

A fully developed square channel flow with a Reynolds number of Re = 4410 (based on bulk velocity and duct width) has been calculated using Large Eddy Simulation (LES) technique with the Smagorinsky eddy viscosity model. Results for the Prandtl’s secondary motion which is turbulence-driven show good qualitative picture and are in good quantitative agreement with values from other authors. Diffe...

A parameterization of mesoscale eddies in coarse-resolution ocean general circulation models (GCM) is formulated and implemented using a residual-mean formalism. In that framework, mean buoyancy is advected by the residual velocity (the sum of the Eulerian and eddy-induced velocities) and modified by a residual flux which accounts for the diabatic effects of mesoscale eddies. The residual veloc...

A non-hydrostatic code that numerically solves the unsteady, three-dimensional, primitive equations is used. Advanced models such as the dynamic mixed model and the dynamic eddy viscosity model are utilized to represent subgrid processes in the LES approach. A novel near-wall model has been developed so as to increase the Reynolds number of boundary flows to realistically large geophysical valu...

secondary flow investigation could be regarded as an important issue in open channel flow, in spite of its lower quantity compared to the base flow in the water course. it should be given special consideration because of the influence on some hydraulic factors in open channel, specifically in compound channels. in compound channels' due to the difference in the flow velocity of the main ch...