note on the effect of thermal radiation in the linearized rosseland approximation on the heat transfer characteristics of various boundary layer flows

in the latter years the title problem has been examined in a large number of research papers. the present note emphasizes, however, that the effect of thermal radiation in the linearized rosseland approximation is quite trivial, both physically and computationally. namely, it always reduces to a simple rescaling of the prandtl number by a factor involving the radiation parameter. this implies that a comprehensive study of the prandtl-number dependence without thermal radiation effects represents per se a detailed study of the radiation effects, too. in other words, the solution of the radiation problem for optically thick media in the linearized rosseland approximation does not require any additional numerical or analytical effort compared to the same problem without radiation, making in this respect dozens of papers superfluous.