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Show NOx FORMATION MODELLING IN OXYGEN-NATURAL GAS INDUSTRIAL FLAMES B. Labegorre1, O. Marin2, O. Charon2, J. M. Samaniego1 and T. Oguro3 Abstract This study investigates the ability of a recently developed model to assess the N O emissions of industrial oxygen-natural gas burners. Numerical simulation results are compared to experimental dataHl for turbulent diffusion flames from 1 M W pipe-in-pipe burners, fired in both a water-cooled and a refractory-lined furnace. The study compares NOx concentration measurements to the predictions of the model developed by Air Liquide (AL model), both in-flame and in the flue gas exhaust. Results obtained with alternate models such as the Fluent^ software, and the model developed by Peters and Weber^] (PW model) are also analysed and discussed. It is noted that IFRF is currently developing an improved NOx model for oxy-flames. The results include different burner momenta and furnace temperatures, assessing the impact of these operating conditions on NOx emissions. The results show that the AL model leads to improvements in assessing NOx formation in natural gas - oxygen combustion, attributed to the employment of a specific kinetics model for high temperature diffusion flame. Additionally, the model takes into account the correlation between specie and temperature fluctuations in the flame. Differences between simulation and measurements are primarily attributed to limitations in predicting the m e a n temperature and in modelling the effects of temperature fluctuations on NOx reaction rate. "Combustion Department, Air Liquide, Centre de Recherche Claude-Delorme, Les Loges-en-Josas, B.P. 126, 78350 Jouy-en- Josas, France. 2Combustion Department, American Air Liquide, Chicago Research Centre, 5230 S., East Avenue, Countryside IL 60525, USA. 3Teisan K. K., Harima Technical Center, Harima, Japan. |