A posteriori analysis of flame surface density modelling for combustion noise prediction in premixed flames

Abstract

The ability of large-eddy simulation (LES) to capture premixed flame acoustics is studied for a turbulent, premixed, round jet flame. Central finite differencing schemes are used with artificial damping. The flame surface density (FSD) approach is used as the combustion model for the reaction progress variable. The effects of combustion modelling and the spatial discretisation scheme order on the flame shape and the sound pressure level (SPL) spectra are examined. It is shown that the FSD approach does not correctly capture flame annihilation. This is where the progress variable gradient decreases as two flame surfaces approach each other. A significant impact of FSD modelling on the SPL is ..