Air Change Effectiveness with Displacement Ventilation System ✓ Most Recent

Stratified air distribution systems such as Displacement Ventilation (DV) have been known to provide better indoor air quality than overhead (mixing) system. Previous research has shown that this type of system works well for regions where buildings require year-round cooling. With a growing number of buildings using DV in Canada, where buildings require heating during winter months, further research on performance was required. This investigation compared, experimentally, the air change effectiveness of a DV system that uses an interior corner diffuser configuration, to an overhead (mixing) system. The experiments were conducted in an indoor environment research facility that simulates an open concept office space (6 cubicles). We measured air-change effectiveness of the performance of DV systems based on tracer gas step-up and decay methods. The DV systems had higher air change effectiveness than the mixing system. The study found that the air-change effectiveness at breathing zone was higher than that predicted in previous studies for heating conditions. The experimental results studies provide some evidence of IAQ-related benefits of displacement ventilation in cold climate.