THE THEORY OF RADIATIVE HEAT-TRANSFER IN DISPERSE MEDIA

A new phenomenological approach is proposed to the description of ener gy transfer by proper thermal radiation in disperse media, which is fr ee of the limitations of geometrical optics and is capable of describi ng collective effects. The approach is formulated in terms of the symb ol (Fourier transform of Green's function) of the operator of radiativ e heat transfer. The properties of the symbol are derived from the con siderations of symmetry and laws of thermodynamics. A correlation is e stablished between the proposed approach, the classical equation of ra diation transfer, and a number of other models. The possibility is dis cussed of practical realization of the proposed approach by generaliza tion of the methods of spherical harmonics and discrete ordinates. The singularities of the symbol are analyzed in the case of localized rad iation. A method of direct measurement of the symbol by the temperatur e wave method is proposed.