## 7.20. Soot Model

In the Magnussen soot model (Magnussen and Hjertager [46], it is assumed that soot is formed from a gaseous fuel in two stages, where the first stage represents formation of radical nuclei, and the second stage represents soot particle formation from these nuclei. Transport equations are solved for the specific concentration of radical nuclei, [mol/kg], and for the soot mass fraction, [kg/kg]:

| (7–138)

| (7–139)

The modeling procedure can be grouped into three independent parts:

1. Formation of nuclei and soot particles following the models of Tesner et al., [45]

2. Combustion of nuclei and soot particles

3. Magnussen’s Eddy Dissipation Concept (EDC) for modeling the effect of turbulence on mean reaction rates.

The soot model can be used in either single phase or multiphase flow (MPF) configurations. In multiphase calculations, however, the soot variables cannot be a separate phase but must be assigned to one of the fluids.

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