A. Helte, 4TH-ORDER BOUNDS ON THE EFFECTIVE CONDUCTIVITY FOR A SYSTEM OF FULLY PENETRABLE SPHERES, Proceedings - Royal Society. Mathematical and physical sciences, 445(1923), 1994, pp. 247-256
An expression for the intersection volume of four equi-sized spheres i
s derived. This expression is used to construct the four-point correla
tion function for a system of fully penetrable spheres dispersed in a
matrix. The knowledge of this four-point correlation function enables
us to numerically calculate the microstructural parameter Bdouble dagg
er, that appears in the fourth-order bounds on the effective conductiv
ity due to Phan-Thien & Milton (Proc. R. Soc. Land. A 380, 333 (1982))
.