Abstract
Recently, as a soot formation model, the method of moments (MOM) for soot particle size distribution function (PSDF) is used in many studies. In this method, soot number and mass densities transport equations are solved to predict the soot formation behavior. In addition, the soot formation is regarded as the combination of major four processes such as nucleation, coagulation, surface growth and oxidation, and the concentrations of soot precursors needed in the nucleation are predicted using the detailed or reduced mechanisms of chemical reactions. In this paper, the soot formation models are reviewed and an example of the numerical simulation of soot formation in a combustion field is introduced. The soot formation in a spray flame is targeted here. The results show that the soot is formed in the spray diffusion flame region and its radiation emission increases with the equivalence ratio of the droplet fuel. This trend is in good agreement with that of the luminous flame behavior observed in the experiment. The radiation is found to strongly affect the soot formation behavior. Without the radiation model, the soot volume fraction is fatally overpredicted.
