Owing to the strong interaction between turbulence and combustion, it is particularly challenging to accurately predict local flame extinctions in a turbulent flame at high Reynolds numbers. Subgrid-scale (SGS) parameterization… Click to show full abstract
Owing to the strong interaction between turbulence and combustion, it is particularly challenging to accurately predict local flame extinctions in a turbulent flame at high Reynolds numbers. Subgrid-scale (SGS) parameterization and model for calculating the filtered reaction rates are the main determinants of an accurate large-eddy simulation (LES) of turbulent flow. This study integrates the recently introduced gradient-type structural SGS models with a simplified partially-stirred-reactor approach to simulate a piloted partially premixed jet flame, Sandia Flame F. An advantage of using the nonlinear SGS models is that they can provide reverse energy transfer from subgrid to resolved scales. To quantitatively understand the performance of the LES framework, we have comprehensively compared temperature and mass fractions of major and minor species with experimental data. The statistics of the simulated field show good agreement with measurements and a notable improvement over previous simulations. Results support the assertion that the proposed nonlinear LES framework can capture extinction and re-ignition in turbulent flames with reasonable computational cost.Owing to the strong interaction between turbulence and combustion, it is particularly challenging to accurately predict local flame extinctions in a turbulent flame at high Reynolds numbers. Subgrid-scale (SGS) parameterization and model for calculating the filtered reaction rates are the main determinants of an accurate large-eddy simulation (LES) of turbulent flow. This study integrates the recently introduced gradient-type structural SGS models with a simplified partially-stirred-reactor approach to simulate a piloted partially premixed jet flame, Sandia Flame F. An advantage of using the nonlinear SGS models is that they can provide reverse energy transfer from subgrid to resolved scales. To quantitatively understand the performance of the LES framework, we have comprehensively compared temperature and mass fractions of major and minor species with experimental data. The statistics of the simulated field show good agreement with measurements and a notable improvement over previous simulations. Results...
               
Click one of the above tabs to view related content.