Large Eddy Simulation of Lean Premixed Swirling Flames via Dynamically Thickened Flame Model Coupling with the REDIM Chemistry Table

Abstract

In this paper, the so-called REDIM–DTF sub-grid scale combustion model is proposed to improve the well-known dynamically thickened flame (DTF) combustion model by combining the DTF modeling strategy with the reaction-diffusion manifold (REDIM) chemistry table, which is generated from a detailed reaction mechanism. The new model is then used to calculate two lean premixed swirling flames in the PRECCINSTA combustor via large eddy simulation. The radial profiles of velocity, temperature, and species concentration, as well as the flame surface area and vortex structure are analyzed. The results are in good overall agreement with the corresponding experiment, and the performance of the REDIM–DTF model is very similar to that of the DTF model. The predicted CO mass fraction profiles, however, show a relatively larger discrepancy between the original DTF model and the proposed REDIM–DTF model, which is thought to be due to different reaction mechanisms used. As a smaller number of species transport equations are solved in the REDIM–DTF model, its computational efficiency is about 15% higher than that of the original DTF model.