Contamination distribution in displacement ventilation—influence of disturbances

Abstract

Tracer gas measurements have shown that in a room with displacement ventilation pollutants can be locked in at different levels. Sometimes well defined layers of pollutants can be found. The distribution is very sensitive to disturbances; opening and closing of a door can cause a great decrease in the local ventilation effectiveness. In spite of this, or perhaps because of this, a person can obtain a good air quality in the breathing zone, even if this zone is in a polluted layer. The convective plume around a body breaks through the polluted layers very rapidly.