Asymptotic regimes and structure of concentration tails in the Dykhne model

A transport problem is solved for a high-contrast regularly inhomogeneous medium. Transport regimes and structure of the concentration tails in high-permeability regions are analyzed for two geometries of such regions: a plane layer and a right cylinder. It is shown that changes with time of transport regimes lead to complex asymptotic particle distributions at long distances (concentration “tails”). The time dependence of the total number of active particles and depth of particle penetration into the low-permeability region are calculated.