Fig xA Comparison of the mole fraction profiles of small

Fig. 5b shows the axial soot concentration in the four flames. The horizontal axis is the flame height and the vertical 'PD axis is the soot concentration in the central line of the flame. It can be seen that the trend of the soot concentration in the central line is consistent with that of the soot distribution shown in Fig. 5a. The peak positions are the same in the three alcohol-TRF flames, at about 38 mm.