Radiant-interchange configuration factors between various selected plane surfaces

The radiant-interchange configuration factor F1-2 (later referred to simply as ‘factor’) is defined as the fraction of the energy leaving an isothermal area Ax that is incident upon another area A 2. The validity of Lambert’s law of diffuse radiation is assumed. The calculation of such factors in the case of two rectangles having a common edge and forming an arbitrary angle is discussed, and a table of calculated values is presented. It is shown how the factors for two parallel, convex polygons, forming the bases of a right prism , can be derived from the results obtained for the rectangles. Values of such factors for a number of regular polygons are tabulated . A separate table gives factors for the honeycomb structure, much used in aviation and aerospace. The importance of much greater accuracy in the calculations than is generally thought necessary is shown by an example.