A Study of Effective Thermal Diffusivity of Dispersed Composite Materials

Macroscopic Homogeneity and Clear Graphical Expression

Abstract

The effective thermal diffusivity of dispersed materials has been studied by numerical simulation on the random model that has macroscopic homogeneity and isotropy. The two kinds of thermal diffusivity are obtained by pulse heated method (direct value) and by eq. (1) used thermal conductivity calculated from steady state comparison method (indirect one). These values are compared each other and we estimate critical condition for macroscopic homogeneity. We propose also clear graphical expression that is shown by the nondimensional thermal diffusivity vs. the ratio of specific heat capacity of particle to matrix.