Numerical study of spectral behavior of boundary surfaces on conbmined radiative convective heat transfer

This study presents a numerical investigation of laminar combined radiative-convective heat transfer in a 2-D rectangular duct. The radiating gas is assumed a mixture of air with CO2 and H2O. The bottom wall made by Silicon and Germaniumis assumed to be spectral and the top surface is gray. The effect of increase in surface temperature and mole fraction of gas mixture on the thermal behavior of such system under the spectral behavior of the boundary surfaces is carried out. Fot thid purpose, in the numerical computations, the energy equation is solved numerically by the well-known finite volume method; while for computation of the radiative term in the gas energy equation, the radiative transfer equation (RTE) is solved numerically by the discrete ordinate method (DOM). It is revealed that increase in mole fraction of gases mixture for Germanium case causes an increase in the value of total heat flux from the bottom surface.