Large eddy simulation of turbulent lean premixed jet flame

Chemistry tabulation combined with presumed probability density function (PDF) was applied to investigate the stabilization mechanism and flame structure of piloted premixed jet burner (PPJB) with high Karlovitz (Ka) number using large eddy simulation (LES). Thermo-chemistry states were tabulated using the autoignition model. Presumed PDF was used to involve the interaction of turbulence and chemistry. Dirichlet distribution was applied for the joint PDF of the two mixture fractions, and beta PDF was used to model the reaction progress variable distribution. The LES results show that distribution of temperature and mass fractions of major species are in good agreement with the experimental data. The mass fractions of intermediate compositions (CO and OH) were applied to describe the flame structures qualitatively, and it is found that the turbulence eddies can affect the inner flame structures with high Ka number.