Abstract
Radiation codes have been developed based on the S 2 and S 4 discrete ordinates approximations which involve solving the radiation transport equation in 4 and 12 directions, respectively. Evaluation of the codes against exact numerical solutions and experimental data show that both these approximations predict radiative fluxes with acceptable accuracy. The models are also evaluated treating them as part of an overall predictive scheme for pulverized coal combustion. The comparative importance of the various input parameters on the model predictions is evaluated via a detailed sensitivity study based on Fourier analysis technique. This analysis shows that the predictions arc most sensitive to the particle number densities and temperatures, while little sensitivity to the absorption and scattering efficiencies is detected.