In this paper the processes of admixture convective diffusion in two-phase structures with periodically located thin channels are investigated with taking into account a natural decay of migrating substance. With the help of application of appropriate integral transforms separately in the contacting domains, a solution of the contact initial boundary value problem of convective diffusion of decaying substance is obtained. The correlations between these integral transforms are found using the non-ideal contact conditions imposed for the concentration function. Expressions for decaying particle flows through arbitrary cross-section of the body are found and investigated, and their numerical analysis is carried out in the middle of both domains — the thin channel and basic material. It is shown that the decay intensity of the migrating substance especially affects the flow distribution in the domain of basic material.

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