Effect of mixing methane, ethane, propane and ethylene on the soot particle size distribution in a premixed propene flame

The fuel mixing effect on soot formation was investigated based on a premixed propene flame, in which the C/O mole ratio was 0.6 and the maximum flame temperature was 1829 K. Different proportions of methane, ethane, propane and ethylene were mixed into the propene flame, with the constant C/O mole ratio and similar maximum flame temperatures and temperature-time histories. The particle size distribution function (PSDF) was measured in the burner stabilized stagnation (BSS) flame configuration, using the micro-orifice probe sampling technique and the scanning mobility particle sizer (SMPS). It was observed that the PSDF of the propene flame was not sensitive to methane, ethane or propane addition, while the number density of small nucleated particles was strengthened with ethylene addition. The particle growth in flame with a small amount of ethylene addition was stronger than that of either the pure propene or ethylene flame, indicating the synergistic effect between propene and ethylene on soot formation.