Performance evaluation of different air distribution systems for removal of concentrated emission contaminants by using vortex flow ventilation system

An excellent air distribution system is a key factor to maintain indoor air quality, particularly in high-concentration contaminant-released buildings such as industrial halls. This study evaluated the performance of a new type of air distribution system, the vortex flow system, for contaminant removal and compared it with three other commonly used air distribution systems. The airflow fields and distribution of contaminants in large-space buildings with concentrated contaminant sources were studied. In addition, the mean age of air (MAA), air change efficiency, ventilation effectiveness, and mean residence time (MRT) of the contaminants were used to evaluate the four air distribution systems. The results of this study illustrated the significance of the air distribution system on the ventilation performance. Owing to the flow characteristics of the column vortex, the contaminants released from the source in the vortex flow system were limited by the negative pressure gradient near the center of the vortex zone and rapidly moved upward along the vortex core, resulting in a higher ventilation efficiency of contaminant removal with a lower ventilation flow rate. The results demonstrated the application potential of the vortex flow system in large-space buildings with concentrated emission contaminants.