An hybrid transported-tabulated strategy to downsize detailed chemistry for Direct Numerical Simulation

Abstract

As trategy to bridge the gap between hydrocarbon combustion detailed chemistry and Large Eddy Simulation (LES) of burners is reported. Significant progress has been made recently in terms of accuracy and robustness in both chemical kinetics and flow computations. However, the highest resolution reached in LES of practical burner does not yet ensure that the response of intermediate radical species is fully captured. In the method discussed, the full set of species and elementary reaction rates of the detailed mechanism are retained, but only species featuring non-zero concentration in fresh and burnt gases are transported with the flow. Intermediate chemical species, developing within thin flame layers, are expressed resorting to their self- similar properties observed in a series of canonical combustion problems. The method is tested with success in various adiabatic or non-adiabatic laminar and strained flames.