Numerical Study of Chemical Kinetic and Radiation Model Effects on the Velocity and Temperature Fields in Natural Gas- Oxygen Combustion by Using of Steady Flamelet Model

The aim of this study was to investigate the effect of chemical kinetics and radiation model on the simulation of natural gas- oxygen combustion by using flamelet combustion model. For this purpose, C1_C3, DRM22 and GRI3.0 chemical kinetics in order to kinetically investigation and the radiation model effect has been used from two radiation model DO and P1. Also, results from the consideration of radiation heat transfer with non-radiation conditions are compared. The results of flamelet combustion model have been compared with the experimental data and PaSR combustion model. The most important advantage of using flamelet combustion model over the PaSR model is a significant reduction in the cost of calculation. According to obtained results, C1_C3 chemical mechanism predicting temperature distribution in furnace with highest accuracy and flame shape created by it has good match with PaSR model simulation; While the obtained flame length with DRM22 and GRI3.0 chemical mechanisms predicted very low. In addition, the use of P1 radiation model in comparison with DO model due to prediction of higher radiation losses in it leads to more computational errors in calculating the temperature distribution as well as the prediction of the length of the high temperature region in furnace.