TY - SER AU - Wolf, Jeffrey R. AU - Tseng, Josefina W.C. AU - Strieder, William. TI - Radiation Conductivity for a Random Void-Solid Medium with Diffusely Reflecting Surfaces SN - 0017-9310 KW - Radiation Conductivity KW - Random Void KW - Solid Medium KW - Diffusely Reflecting Surfaces N2 - A variational principle is formulated for radiant heat transfer through the void spaces and conduction in the solid, of an arbitrary void-solid system with diffusely reflecting surfaces. Variational upper bounds on the effective conductivity of a void-solid suspension are expressed in terms of certain averages characterizing the random geometry. A radiation conductivity upper bound, calculated for a model porous medium generated by randomly placed, overlapping spheres, is compared with well-known results from kinetic theory and radiant heat transport. The variational principle provides a means to obtain useful estimates and upper bounds on the thermal radiation conductivity, that include multiple and anisotropic diffusive scattering in a bed of large particles UR - https://www.sciencedirect.com/science/article/pii/001793109090170Y ER -