Infiltration through leaks? A careful analysis of minimum air change according to DIN 1946

Purpose of the work

Can the minimum air change in naturally window-ventilated units be covered only through leakages?

Content of the presentation

In general, the infiltration airflow rate is dependent on meteorological conditions, especially wind pressure on the building / unit, and with regard to thermal effects, the temperature differential between the interior and the exterior, i.e. the infiltration airflow varies strongly.

The effects of leakages in roofs with ventilated air layers - a CFD approach

The following paper is focused on hygrothermal behaviour of roofs with ventilated air layers subjected to air leakages in their internal decks (the internal partial construction located below the ventilated air layer). Possibilities of CFD modelling of such constructions are discussed in the first part of the paper including the problem of introduction of water vapour diffusion into calculation. A brief comparison of results from CFD analysis and from calculation based on a technical standard is also included.