RE: [EnergyPlus_Support] Infiltration

["Edward G. Lyon" <eglyon@xxxxxxx>]

In my opinion, the answer to your question is very complex.  I am not sure what you mean precisely by 50Pa test.  Usually this means ACH50 (air changes per hour at 50 Pa), but you could have a complete test that reports Coef and Expon for the flow equation Flow = Coef*Pressure^Expon.



In either case there is no short cut way I see to put this data directly into EnergyPlus.



I also think different procedures may apply to different types of buildings.  If you have a small house, and ACH50 result divided by 20 (sometimes other factors) is a fair approximation of the infiltration air exchange rate for a small building.  You could define Infiltration as an ACH and juggle the coefficients to give you a better guess for seasonal temperature and wind conditions.  Or you could study the research on ACH50 correlations to infiltration and schedule something appropriate for your location.  If you have a commercial building, your test data should be unit area based and you would use Infiltration with a surface area calculation.



Infiltration in EnergyPlus has a sophisticated set of input parameters intended to vary infiltration by site conditions, and I have done a lot of whole building testing.  Perhaps others can provide a good reference for integrating measured data into the energy model, but I have not seen it.  I think there may a way to approximate the pressure from the temperature and wind in order to recalculate coefficients for Infiltration in EnergyPlus.  Perhaps I need to study this in more depth myself.