P. Markatou et al., A COMPUTATIONAL STUDY OF SOOTING LIMITS IN LAMINAR PREMIXED FLAMES OFETHANE, ETHYLENE, AND ACETYLENE, Combustion and flame, 93(4), 1993, pp. 467-482
The onset of sooting in laminar premixed flames was examined computati
onally. Three series of atmospheric fuel-oxygen-nitrogen flames of eth
ane, ethylene, and acetylene were simulated using a detailed chemical
kinetic model of soot particle nucleation and growth. It was found tha
t the critical equivalence ratios for soot appearance, both the absolu
te values and temperature dependencies, can be predicted fairly close
to the experimental observations, even when no reactions for the oxida
tion of aromatics by hydroxyl are included in the mechanism. The analy
sis of the computational results strongly suggests that the appearance
of soot is controlled by two factors, concentration of acetylene and
growth of polycyclic aromatics, and the latter is limited by the rise
in flame temperature towards the end of the main reaction zone. The pr
esent results and conclusions are in agreement with the principal find
ings of previous modeling studies.