Non-Gray Radiative Heat Transfer in Two-Dimensional Cylindrical System

Radiative heat transfer in a concentric cylinder system with a participating medium is demonstrated to be inherently two-dimensional, even for the consideration of heat transfer to the total inner or outer surface with uniform boundary conditions. For the evaluation of two-dimensional nongray radiative heat transfer, the zonal exchange factor, together with the concept of point mean beam length, is shown to be an effective solution approach. Optimal point mean beam length for radiative heat transfer between a differential area and a finite area with different geometrical configurations within the concentric cylindrical enclosure is generated. Numerical data for an example calculation is presented to illustrate the characteristics of nongray two-dimensional radiative heat transfer.