The ignition, combustion and flame structure of carbon monoxide/hydrogen mixtures. Note 2: Fluid dynamics and kinetic aspects of syngas combustion

The kinetic characterization of the H2/CO system in presence of nitrogen components was systematically revised in the first note of this work [Frassoldati A, Faravelli T, Ranzi E. The ignition, combustion and flame structure of carbon monoxide/hydrogen mixtures. Note 1: detailed kinetic modeling of syngas combustion also in presence of nitrogen compounds. Int J Hydrogen Energy; 2007, in press]. This second note analyses three different turbulent non-premixed syngas flames by using different approaches such as the Eddy dissipation (ED) the Eddy dissipation concept (EDC) and steady laminar flamelets (SLF) model.Detailed kinetic schemes are too large and computationally expensive to be directly applied to CFD codes. Pollutants marginally affect the main combustion process and consequently it is feasible to post-process the CFD results with large detailed kinetic schemes, capable of accurately predicting the formation of pollutants, such as NOxNOx, CO, PAH and soot. Thus, in order to predict NOxNOx formation in these flames, a detailed kinetic scheme is applied by means of a newly conceived numerical tool: the kinetic post-processor (KPP).The successful prediction of flame structures and NOxNOx formation supports the proposed approach and makes the KPP code a useful tool for optimizing the design of new burners.