A Computational Study of the Soot Formation in Methane-Air Diffusion Flame During Early Transience Following Ignition

act— A CFD-based numerical model has been ed for the determination of the volume concentration ber density of soot in a laminar diffusion flame of in air, under transient condition following ignition of e. The transience is studied from the point of ignition final steady state is reached. The burner is an axiric co-flowing one with the fuel issuing through a port and air through an annular port. Both normal air eheated) and preheated air have been used for this on to capture the effect of preheating on soot tion. Attention is focused on various soot forming and ion processes, like nucleation, surface growth and n, during the transient phase to evaluate their relative nce. The transient soot distribution has been studied help of radial distributions of soot at six different axial of 2 cm, 4 cm, 6 cm, 8 cm, 10 cm and 12 cm vely above the burner tip. Beyond 12 cm height, the ration becomes very less in all cases. The contribution ce growth towards soot formation is more significant at of nucleation during the early periods following . Once the high temperature reaches the oxygenzone beyond the flame, the soot oxidation becomes nt. Coagulation, on the other hand, limits the soot number. Preheating of air increases the soot volume in the flame significantly. But, the soot distribution remain almost similar to that with non-preheated air he flame transient period and also in the steady state.