PARAMETRIC STUDIES OF THE EFFECTIVE OPTICAL CHARACTERISTICS OF TRANSPARENT 2-COMPONENT MATERIALS BASED ON A MODEL REPRESENTATION OF THEIR BULK STRUCTURE

A statistical analysis of analytical methods of exact and approximate calculation of radiative transfer in laminated structures is made on t he basis of a model representation of a multilayered stack of monolith ic plates with gaps in the form of a Layer of an isotropic material. T he stack is characterized by a corresponding level of porosity. It is established that it is possible to reliably describe the optical prope rties of the layer by commonly used methods - including the two-flow, and backscattering, and diffusion approximations - if an invariant app roach is used to determine the corresponding effective values of refra ctive index, the volume absorption coefficient, and the scattering coe fficient. It is shown that it is not possible to take effective optica l characteristics determined in one approximate method and use them in another such method. Parametric calculations are performed to study t he effect of the thickness of the individual plates, the refractive in dex, and the volume absorption of the monolithic material on the effec tive characteristics and optical properties of the porous layer.