Diagnosis of Turbulence Radiation Interaction in Turbulent Flames and Implications for Modeling in Large Eddy Simulation

Authors: DAMIEN POITOU, MOUNA EL HAFI, BENEDICTE CUENOT

Abstract: An a priori study of the turbulence radiation interaction (TRI) is performed on numerical data from Direct Numerical Simulation (DNS) of a turbulent flame. The influence of the various correlations that appear in the radiative emission is investigated and their impact is evaluated in the context of Large Eddy Simulation (LES). In LES, only filtered quantities are computed, where the filter is the grid. The radiative emission is reconstructed first from the exact, then filtered solution variables and the sensitivity to the filter size is evaluated. Three approaches are used to take into account the subgrid scale correlations: the no-TRI, partial TRI and full TRI approaches. Results show that the full TRI is exact compared to the reference emission and that the partial TRI performs worse than the no-TRI for the studied configuration. This indicates that in the studied case, the TRI must be considered in LES in a full formulation.

Keywords: Turbulence-Radiation Interaction, Large Eddy Simulation, turbulent combustion, radiative transfer

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