Comparison of different WSGG correlations in the computation of thermal radiation in a 2D axisymmetric turbulent non-premixed methane–air flame

Abstract

This study makes an analysis of the radiation heat transfer in a turbulent non-premixed methane–air cylindrical combustion chamber. The highly complex dependence of the radiative properties with the wavenumber spectrum is modeled with the weighted-sum-of-gray-gas (WSGG), making use of the classical correlations of Smith et al. (J Heat Transfer 104:602–608, 1982) and of the more recently in obtained correlations of Dorigon et al. (IJHMT 64:863–873, 2013), based on HITEMP2010. The reaction rates were considered as the minimum values between the Arrhenius and Eddy Break-Up rates. A two-step global reaction mechanism was used, and turbulence modeling was considered via standard k–e model. The source terms of the energy equation consisted of the energy involved in the reaction rates and radiation exchanges. The discrete ordinates method (DOM) was employed to solve the radiative transfer equation (RTE). The results show that the temperature, the radiative heat source, and the wall heat flux can be importantly affected by the WSGG correlations, while their influence on the species concentrations tends to be negligible. Numerical results considering the WSGG model with the new correlations were closer to experimental data presented in the literature.