TRANSPORT THROUGH RANDOM ARRAYS OF CONDUCTIVE CYLINDERS DISPERSED IN A CONDUCTIVE MATRIX

We present computer simulation results for the effective conductivitie s of random dispersions of cylinders of arbitrary conductivity relativ e to that of the matrix phase. The cylinders are randomly positioned i n space with their axes parallel to a line, parallel to a plane, or wi thout preferred orientation. Effective conductivities are computed fro m the mean square displacement of carriers traveling in the two-phase medium according to a discrete step-by-step random walk mechanism. The probability that a carrier colliding with the interface will be refle cted back into its phase of travel or cross into the other phase is de termined on the basis of the conductivities of the two phases meeting at the interface. The computed values of effective conductivity are co mpared with variational bounds and analytical approximations of the li terature. (C) 1996 American Institute of Physics.