Survey of Control Characteristics of Circular Air Dampers in Variable Air Volume Ventilation Systems

Due to the fact that importance of energy efficiency of building services is consistently growing also demand based VAV ventilation systems are becoming more common. Almost all available terminal VAV dampers on the market are single blade dampers, but is this damper configuration the most suitable for VAV functionality? The aim of this study was to test the control characteristics of the most widespread circular damper configurations. The results show that under typical operation conditions IRIS diaphragm type damper control characteristics are the most suitable for VAV functionality in means of linearity between damper opening position and relative air flow.