Directional Emissivities Of Semi-Transparent Media. Cases Of Dihedron, Infinite Cylinder And Cone

The apparent spectral directional and hemispherical emissivities of simply shaped semi-transparent media (parallel slab, sphere, dihedron, infinite cylinder, cone) are calculated by a ray-tracing technique. The method is fairly general and adapted to several geometrical coordinate systems (absolute or local) according to the nature of the surface. It includes an accurate description of the physics of the radiative transfer in the presence of multi-reflections and total reflection phenomena.