Infrared radiative heat transfer in nongray nonisothermal gases

In the present paper, both nongray and nonisothermal behaviors of an infrared emittingabsorbing gas have been taken into account in radiative transfer analyses through the use of the nonisothermal band absorptance. Consideration is given specifically to a simple system consisting of a radiating medium bounded by two infinite parallel black surfaces of different temperatures. Solutions are presented for the cases of radiative equilibrium and combined conduction and radiation. Results based on different methods of evaluating the nonisothermal band absorptance are also compared among themselves. Differences in several fundamental features are exhibited in the nongray nonisothermal solutions as compared to those with nongray but isothermal properties.