simulated (using CONTAM) not assumed。 Annual hourly air infiltration rates for the whole buildings are obtained。

Air infiltration rates obtained for each building zone are input in EnergyPlus replacing all original infiltration inputs in the model。

It is important to note that in each of the four methods, single and vestibule door cases are both simulated。 In CONTAM, entrance doors are modeled using the one way flow – power law model, where the flow coefficient is the door coefficient [5], C, and the flow exponent is equal to 0。5 [9,13,25]。 In EnergyPlus, when using methods  1,  2  and  3,  door  infiltration  is  modeled  as  design rate

2。3。 Air infiltration calculation and modeling

As mentioned previously, four methods are used to calculate air infiltration through doors in this study。 The detailed calcula- tion/simulation process of each method is as follows (details seen in Table 4):

1。 Design Method – Based on the assumptions described previous, the  door  infiltration  rates  in  the  two  buildings  are calculated

in Zone Infiltration category [4]。 When using the Yearly CONTAM Method (method 4), a process of zone matching was required due to some differences between the airflow models and the energy models were found [22]。 When using method 4, the infiltration rates obtained from CONTAM (hourly infiltration rates by zone) are modeled in EnergyPlus as design rate in Zone Infiltration category and replace the original infiltration inputs in the energy model。 The changes made to the original CONTAM and EnergyPlus models are detailed in Table 5。

Table 5

Changes made to the original CONTAM [22]and EnergyPlus models [15]。

Modeling Method CONTAM EnergyPlus

Design Method NA The original door infiltration rates and   schedules

Seasonal Design Method

are replaced by the calculated infiltration rates based on 2 m × 2。4 m door。 The door usage frequency is 100 Ph (except the sensitivity study when the usage is varied) and the doors are used from 8 AM to 8 PM。 The infiltration is modeled as design rate in zone infiltration category。

Seasonal CONTAM Method Single and vestibule door models (2 m × 2。4 m) are The original door infiltration rates and schedules

added to the CONTAM models and modeled using  are replaced by the infiltration rate obtained from

the power-law model based on Yuill’s findings [5]。 CONTAM。

Yearly CONTAM Method

The door usage frequency is 100 Ph (except the

The original door infiltration and wall leakage is

sensitivity study when the usage is varied) and the removed。 The hourly zone infiltration rates for the

doors are used from 8 AM to 8 PM。

whole year is used in the energy models and is used as design rate input in zone infiltration category。

Table 6

Door coefficients, C, for the single and vestibule doors of 2 m × 2。4 m at varying door usage frequencies, Ph, based on Yuill’s study [5]。

Table 7

Pressure difference, 6P, for different outdoor temperatures across the door for the two building models calculated based on Rp obtained from ASHRAE [8]。

Ph Single Door Vestibule Door

Outdoor Temperature (◦ C) Entrance Pressure Difference (Pa)

0