Formation of Thermal NO_x in Tangential Combustion and NO_x - Reduction by Water Spray

Abstract

Tangential combustor using propane-air mixtures was utilized to investigate the formation of thermal NO_x and the effect of water - spray on NO_x reduction. Measurements of temperature and NOx concentration in combustor were made in detail along both axial and radial directions, so as to comprehend the correspondence of NO_x formation with gas temperature and the effect of water spray on the temperature distribution in the combustor, which strongly affects NO_x formation.
Combustor for this work was made to prevent back-mixed flow as far as possible, so that NO_x formation in post-flame gas could be distinguished from that in primary reaction zone. As a result, for the former, formation of NO_x could be expected to follow the Zeldovich mechanism and, for the latter, NO_x formation was independent of gas temperature and consequently no effect of water spray on NO_x reduction was observed.