Modelling of light extinction by soot particles

A simplified model for the prediction of light extinction through combustion generated smoke is presented. The model builds upon existing theory and available experimental data to account for the principal factors that influence light extinction in participating media, including wavelength, primary particle size distribution and morphological structure of particle aggregation as well as multiple scattering among particles within a particle aggregation. Good agreement is demonstrated between the model predictions and experimental data in the visible and IR ranges. The model illustrates that as the mean particle size increases, the integral optical property of a soot cloud approaches that of monodisperse particles. It is postulated in the current study that the number of particles participating in multiple scattering is around 20 regardless of the real size of particle aggregation.