The present work is a numerical simulation results from the modelling of a non-premixed methane fl ame with and
without radiation models. CFD studies using FLUENT code were carried out for three cases; without radiation model,
with the P-1 radiation model and with the discrete transfer radiation model. The model results from these three cases
are compared with each other and with the experimental results. The discrete transfer and of the P-1 radiation models
are assessed in a swirling methane non-premixed flame confined in an axisymmetric combustor. The predictions are
involving the modeling of the combustion and radiation phenomena. Computational results with and without radiation
effects are compared with experimental data and the two radiation models are evaluated in terms of computational
efficiency, ease of application and predictive accuracy. The effects of momentum flux, swirl number and air inlet
temperature on flame characteristics are examined. A comparison of realizable k- and standard k- turbulent
models are presented. The results show the significant effect of studied parameters on the flame characteristics and
temperature patterns.The results have demonstrated that the effect of thermal radiation is important even in flames, and
that the discrete transfer and the P-1 radiation models and realizable k- turbulent model can be applied in industrial
gas furnaces with relative ease, yielding accurate predictions.