An LES subgrid modeling formulation based on a parameterization of the linear-eddy model (LEM) has been employed to assess the sensitivity of model predictions on strain rate effects within a model premixed combustor configuration. This subgrid model directly includes strain rate effects through the application of the LEM to a counter flow configuration. This allows for the estimation of the turbulent flame speed as a function of resolved scale strain rate, as well as for the prediction of turbulent flame extinction limits. Tractability and efficiency of the modeling formulation is achieved through a database driven approach where the LEM is used to perform off-line simulations which are used to populate a database. This database is then deployed within the LES flow solver. This subgrid formulation was applied to a model combustor configuration to parametrically investigate the effects of strain rate and inflow turbulence specification on model predictions. This case was found to be highly dependent of the inflow turbulence specification illustrating the need for highly controlled and comprehensive experimental measurements of the boundary conditions. Strain effects within the context of the inflow turbulence specification were found to significantly affect the predictions as well.

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