FLAME STABILIZATION AND NOX REDUCTIONIN A NON-PREMIXED BURNER WITH SAWTOOTH MIXER

摘要

Sawtooth mixing device used in a non-premixedrnburner is evaluated for flame stabilization andrnNox reduction accomplished by the forcedrnmixing of the fuel and air due to the streamwisernvortices. Three geometries with bladerndeflection angles of 0, 20, 40 degrees (SM0,rnSM20, SM40) are tested. Methane is deliveredrnthrough the fuel jet pipe and air passes throughrnthe co-flow annulus. The flame mode changesrn(attached flame, lifted flame and extinction)rnagainst the fuel flow speed are measured, andrnthe stability diagram is drawn. Moreover, byrntraversing thermocouple and sampling probe inrnthe flame, the distribution of temperature, Noxrnand O2 mole fractions are measured. In therncase of SM0, the flame has the least tendency tornlift and in the case of SM40 the flame has thernleast tendency to extinct. With the change inrnblade angle, flame shape, flame stabilization,rnthe distribution of temperature and Nox molernfractions are changed considerably.