Monte Carlo modeling of radiative transfer in a turbulent sooty flame

The calculation of radiative transfer within a sooty turbulent ethylene–air diffusion jet flame has been carried out by using a Monte Carlo method and an accurate CK model for the gases. The influence of the turbulence–radiation interaction (TRI) has been studied. In the TRI modeling, the radiative properties of the assumed homogeneous turbulent structures are randomly obtained from a multidimensional probability density function (PDF) of the reaction progress variable, of the mixture ratio and of the soot volume fraction. This joint PDF is obtained from an Eulerian–Lagrangian turbulent combustion model and the sizes of the turbulent structures are directly derived from a k–ϵ model. In the considered flame, the TRI effect is an increase of the radiative heat loss by about 30%. The radiative heat loss becomes almost equal to one-third of the chemical heat release. Soot particles play the most important role in the global radiative heat loss but the influence of gaseous species like CO2 and H2O can be important in the local energy balance.