Predictions of soot in laminar diffusion flames

A model for soot formation in diffusion flames is proposed in which a correlation between mixture fraction and soot surface growth rate is used. The correlation is derived from measurements in a stagnation point diffusion flame. The calculation solves the boundary-layer form of the flow equations, which include the continuity equation, momentum, mixture fraction, and the enthalpy equations. The latter equation is included to account for radiation, which earlier studies found to be important in determining the flame temperatures in sooty flames and the rates of soot reactions. Results are presented for two laminar flows. The first is an axisymmetric laminar jet diffusion flame and the second is a Wolfhard-Parker two-dimensional flame. Good agreement has been obtained for both flows without adjustment of the model parameters.