Experimental and modelling study of low-NO<inf>x</inf> industrial burners

The effects of burner geometry and fuel air inlets on NOx formation in an industrial burner identified in experimental and modeling activities was studied. A turbulent methane burner was studied experimentally in flame and flameless combustion modes. It was modelled using a commercial computational fluid dynamics (CFD) code assuming a 2-step kinetic mechanism. CFD results were post-processed using a numerical code called kinetic post-processor, which models turbulent reactive flows with detailed chemistry. Fixed temperature inside the cells reduces high nonlinearity of the system mainly related to the reaction rates and to the coupling between mass and energy balances. NOx emissions predicted at 1200°C correspond to the measurements. Experimental measurement and CFD simulation shows that the modified burner in flameless mode halves NOx emissions.