Wolf, Jeffrey R. Tseng, Josefina W.C. Strieder, William. <br/><br/>
Radiation Conductivity for a Random Void-Solid Medium with Diffusely Reflecting Surfaces 

 - 725-734 p. 
<br/><br/> 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. 
<br/><br/><label>ISSN: </label>0017-9310 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Radiation Conductivity<br/>Random Void<br/>Solid Medium<br/>Diffusely Reflecting Surfaces