Large - eddy simulation with dynamic SGS models 1 Large - eddy simulation with dynamic subgrid - scale modelsM

Diierent dynamic subgrid scale models, viz. the dynamic model of Germano et al. are evaluated by means of a priori tests. Direct numerical simulation data for fully-developed turbulent and transitional incompressible ows are used. Low correlation is obtained between exact and modeled subgrid scale stresses with the DSM. Conversely, good agreement is found for both the DMM and the DTM, since those models explicitely account for the modiied Leonard term, i.e. the resolved part of the subgrid scale stress tensor. However, the addition of a second parameter in the DTM improves the correlation with the exact stresses. Moreover, the high peaks of the dinamically computed eddy viscosity, observed for the DSM, are noticeably reduced with the DMM, and, in a larger extent, with the DTM.