mass flow

Currently in the building industry is trend to build buildings consuming little energy. For the aim reducing heat loss buildings they are building insulated and also air tightness of buildings increases.. By improving the air tightness of buildings, there is a change of indoor air quality in buildings. Without natural or mechanical of ventilation there is a significant deterioration of indoor air quality. For the raising of quality indoor air is optimal system with demand-controlled ventilation using sensing of carbon dioxide.

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.