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Energy Performance of Underfloor Air Distribution Systems

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(PDF file, 82 pages, 1.5 megabytes)



Publication Number: CEC-500-2007-050
Publication Date: July 2007

 

Report Appendices

Appendix A: Part II: Room Air Stratification Full Scale Testing, (PDF file, 82 pages, 2.1 megabytes)

Appendix B: Part II: Laboratory Layouts and Normalization of Room Air Stratification Profiles, (PDF file, 37 pages, 1.4 megabytes)

Appendix C: Part III: The Fluid Dynamics of a UFAD System, (PDF file, 165 pages, 1.9 megabytes)

Appendix D: Part IV: Underfloor Plenum Testing and Modeling, (PDF file, 37 pages, 508 kilobytes)

Appendix E: Part V: EnergyPlus Development, (PDF file, 328 pages, 936 kilobytes)

Appendix F: . Part VI: UFAD Cooling Airflow Design Tool, (PDF file, 22 pages, 368 kilobytes)

 

Abstract

This multi-year project developed EnergyPlus/UFAD, a version the publicly available whole-building 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.



Keywords: underfloor air distribution, UFAD, EnergyPlus, EnergyPlus/UFAD, energy modeling, design tool, room air stratification, cooling load, underfloor plenum, full-scale experiments, salt-tank testing, thermal plumes, thermal comfort