Energy performance of underfloor air distribution systems

This multi‐year project developed EnergyPlus/UFAD, a version the publicly available wholebuilding energy simulation program EnergyPlus that adds the capability for modeling underfloor air distribution systems. The project also developed a practical design tool for determining the cooling airflow quantity for underfloor air distribution systems. EnergyPlus/UFAD and the cooling airflow design tool are the first validated underfloor air distribution system tools of their kind. As such, they represent a significant advance in the state of the art of the design and energy analysis of such systems. This highly collaborative effort involved experts and facilities from four organizations, including the Center for the Built Environment at University of California, Berkeley; University of California, San Diego; Lawrence Berkeley National Laboratory; and York International. This final report and seven appendices present experimental testing and analytical and computational fluid dynamics modeling on room air stratification and underfloor plenum distribution—critical efforts that informed the development of models for EnergyPlus. Also discussed are new implementations of heating, ventilation, and air conditioning systems to support underfloor air distribution system modeling in EnergyPlus and the development of a practical design tool for such systems.