A concept of equivalent absorption and emission coefficients for gray analysis of radiative heat transfer

Abstract

Due to the non-gray of gas radiation, the total emissivity differs from the total absorptivity. Therefore, in gray analysis, the equivalent absorption coefficient is not equal to the equivalent emission coefficient. Based on this idea, in this paper, a concept of equivalent absorption coefficient and equivalent emission coefficients is presented for gray analysis of gas radiative heat transfer. The equivalent emission coefficients are calculated by Leckner's formula and the equivalent absorption coefficients are estimated by inverse analysis. A one-dimensional gas radiation is taken as an example to show the efficiency of this concept. The results show that the concept of equivalent absorption and emission coefficients is feasible. It is necessary to use both the equivalent absorption coefficient and the equivalent emission coefficient for gray analysis.