Generalized two-region model for infiltration studies.

Uses a two-region model to predict infiltration, to take into account non-ideal mixing of tracer gas in a building. Considers versions of this model:< 1. Fluid flows between the 2 regions and the environment in any manner provided steady state and mass balance are maintained.< 2. There is limited interchange between the regions< 3 Air flows into the first region and out of the second with (unbalanced) interchange between the two.< 4. The second region is a "dead-water" zone, which is not directly connected with the outside.<5. Fluid flows in two separate streams through the two regions, which do not interact.< The use of model 3. is illustrated by an example (air change rate in a cold meat store using SF6 as a tracer) in which the model parameters are deduced both from physical reasoning and from a curve-fitting procedure.