Impact of airflow profile on indoor air quality—a tropical study

The validation of the concentration levels of indoor contaminants and the measurement of ventilation parameters with CFD simulation results often poses considerable difficulty due to the effect of several confounding factors. Whilst a building in dynamic operation with varying operating characteristics in terms of the air-conditioning system and the activities of the occupants renders the possibility of a continuous measurement of IAQ and ventilation data, it is almost impossible to simulate such dynamic changes in the CFD environment. It then becomes imperative that steady-state measurements in buildings be used as representative data for the purposes of CFD simulation. This paper reports the findings of a study, in which the simulation of airflow pattern in an office building in Singapore is based on the indoor environmental conditions and the corresponding ventilation parameters measured on a typical day. Boundary conditions are obtained through hood measurements to determine the airflow rate from each diffuser. The findings of this study clearly support the critical impact of airflow on pollutant pathways in the building as a result of air supply volume, arrangement of air inlet and outlet devices, space design and the presence of heat sources.