Modeling of ONERA Experiment with Subsonic Premixed Turbulent Flame in Duct with Backward Step

The premixed subsonic turbulent combustion of methane-air mixture in channel with backward step is considered. (Magre P. et al., ONERA, 1975-1989). These experiments represent basic physical mechanisms, which are common for combustion processes in gas turbine units. The brief review of previous works on numerical modeling of these experiments is presented. The new results of numerical investigation of stable flame regime for this experimental setup are presented. The choice of turbulence model and its influence on flow structure are described. Various approaches for turbulent combustion description, based on PaSR (Partially Stirred Reactor) are compared with quasi-laminar approach. The recommendations are given for choice between global and multistage chemical kinetics in combination with different models for turbulence combustion interaction. The influence of variable turbulent Prandtl and Schmidt number model on this flow representation. The ideas for further research are formulated.