OR-05-05-5 - Effects of Source Type and Location on Contaminant Dispersion in a Displacement Ventilated Room PDF

This research studies the effects of source type and location on contaminant dispersion and exposure in a displacement ventilated room. A full-scale environmental chamber is used to measure the airflow and contaminant distributions in a mockup office setting. A point source is positioned at four different locations to examine the sensitivity of the contaminant distribution to source locations. This is followed by the exposure measurements in the same room with an area of contaminant sources on the floor. Experimental data are used to validate a computational fluid dynamics (CFD) model, and the CFD program is further applied to simulate the contaminant dispersion with more area sources. Results show that the source type and location affects the exposure distributions for both point source cases and area source cases. Unusually high exposures are observed locally in the vicinity of the point source, while this is unlikely to happen in area source cases. It is also shown that even when the contaminant source is at floor level (i.e., unfavorable source location), displacement ventilation can still generate slightly lower concentration at or below the breathing zone compared to completely mixing ventilation.

Units: SI