Energy Saving Characteristics of Hybrid Displacement Ventilation System with Vertical Supply Duct

The study on saving energy is being conducted widely in the ventilation system of industrial building with high-ceiling.         

The mixing ventilation system (MVS) is less effective for the high-ceiling buildings from the view of energy saving. The displacement ventilation system (DVS) has a shortcoming when process equipment with high thermal load is utilized in industrial building.           

In this paper, the characters of indoor airflow and temperature distribution in hybrid displacement ventilation system (HDVS) where the vertical supply duct has been installed on the middle height of the building have been analyzed by computational fluid dynamics (CFD). And the specific influence of the velocity of air inflow and the length of the supply duct on the air temperature has been analyzed, and the existence of the effective length of vertical supply duct in this system has been discovered from the view of energy saving.    

The accuracy of simulated results has been validated comparing with the experimental data. The operation of this system is more cost effective as the temperature of the air in the working zone has decreased 3.2-5.4℃ compared to the MVS.