| Summary: | 碩士 === 國立中央大學 === 土木工程學系 === 104 === Natural ventilation is widely used to improve the indoor air quality and to save energy from mechanical ventilation in buildings. However, hazardous air pollutants (HAPs), such as CO (carbon monoxide), NOx, SOx, and VOCs, could transport in and out of buildings through building openings. This study uses wind tunnel experiments and an unsteady transport model to investigate the transport process of gaseous pollutants in partitioned rooms. The transport rates of gaseous pollutant inside a scale model were measured by the tracer decay technique, and the internal and external pressures were measured by a multi-channel pressure scanner. The effects of external wind speed, wind direction and opening area on the transport rate were systemically investigated in a series of wind tunnel experiments. The experimental results indicate that the influence of model size on the dimensionless exchange rate Q* of shear ventilation is insignificant, and Q* is dependent of opening area A2 and turbulence intensity of the approaching flow. The experimental results were used to validate an unsteady model for gaseous pollutants in partitioned rooms. Then the transport model was applied to evaluate the influences of external wind speed, initial concentration, interior volume and opening strategy on the transient concentration of gaseous pollutants in buildings.
|
|---|
