Airflow and Indoor Air Quality Models of DOE Reference Commercial Buildings

Sixteen reference commercial buildings were defined by the U.S. Department of Energy (DOE) and created as EnergyPlus input files. They were developed for use in assessing new technologies and supporting the development of energy codes. Infiltration rates were inputs to the models, rather than calculated based on established building airflow theory. In order to support more physically-based airflow calculations, as well as contaminant transport analysis, models of the 16 reference buildings were created in the multizone airflow and contaminant program CONTAM. A number of key inputs had to be defined for the CONTAM models, including changes to the interior zoning to account for more realistic airflows. Annual airflow and contaminant simulations were performed in CONTAM for six of the buildings. As expected, the assumed infiltration rates in EnergyPlus did not realistically reflect impacts of indoor-outdoor weather conditions. In contrast, there were clear relationships between the air change rates calculated by CONTAM and weather. The infiltration rates assumed in EnergyPlus were also generally lower than those calculated by CONTAM. Contaminant analyses were also performed for occupant-generated carbon dioxide and volatile organic compounds from indoor sources, as well as for outdoor particulate matter and ozone.