Abstract

Nearly one third of all natural gas is consumed in Bunsen-type burners, partially premixed flames which have a fuel-rich premixed flame forming an inner core surrounded by a diffusion flame. Pollutant emissions of nitrogen oxides, NO_x, in these flames are an important concern. The NO is produced by two chemical pathways, the thermal (Zeldovich) and the prompt (Fenimore) mechanisms. For temperatures below 2000 K, the thermal pathway is minimized because of the high activation energies of the rate-limiting chemical reactions. Thus, at the flame temperatures found in partially premixed flames, the prompt mechanism produces much of the NO.

© 1998 Optical Society of America