Stochastic Simulation of No Formation in Lean Premixed Methane Flames

A stochastic model of combustion and NO_X formation in premixed turbulent methane flames is described. The model is based on the combination of Computational Fluid Dynamics and Monic Carlo methods for the solution of the joint scalar Probability Density Function. Finite chemical rates are represented with several alternative reduced-chemistry systems, of both the global and systematically-reduced types.

The model is applied to the investigation of a lean, premixed, bluff-body-stabilized flame, for which experimental data exist. In these conditions, the prediction of NO formation is very challenging, both because of the very low values (typically a few parts per million), and because all NO formation-routes are relevant. The results obtained show good accuracy for velocities, main species and temperature, and arc very encouraging in respect of minor species, including NO.