Abstract
The diffusion of an admixture substance in a multiphase layer with randomly disposed spherical inclusions was investigated. The solution of the initial contact-boundary value problem is obtained in the form of the integral Neumann series. Computer simulation was performed based on the obtained calculation formula. Main regularities of the distributions of the averaged admixture concentration in the layer depending on the values of the diffusion coefficients, density and volume fractions of inclusions were established. The influence of the number of phases of the porous body on the diffusion processes in a multiphase layer with a uniform distribution of spherical inclusions was determined. The dependence of the increase of the averaged concentration function on the characteristic radii of spherical inclusions was analyzed, in particular, it is shown that the behavior of this function does not depend on the ratios of the reduced diffusion coefficients.