Performance evaluation of personalized ventilation system with two types of air terminal devices coupled with displacement ventilation in a mock-up office

This article presents a study on the performance of personalized ventilation (PV) with the displacement ventilation (DV) system in a mock-up office space. It is an advantage to leverage on the benefits of personalized and displacement ventilations to bring better air quality to the breathing zone with personalized control and improved thermal comfort respectively. A series of experiments were carried out to determine the performance of two types of PV air terminal devices (ATDs), round movable panel (RMP) and a pair of desktop PV ATDs (DATDs), in terms of pollutant transportation characteristics and thermal comfort of the breathing thermal manikin in a room served by a DV system. It was found that the performance of the two PV ATDs is different in terms of inhaled air quality and thermal comfort. RMP was found to provide a wider range of protection and cooling as compared to DATD, which is more localized but more effective in both protection and cooling. In addition, computational fluid dymanics simulations were performed to have an in-depth understanding on the effect of PV air temperature on the performance of the PV-DV coupled system. It was found that the simulated data correlates well with the measured data. Simulated data shows that the optimum airflow rate for RMP is around 10 L/s. On the whole, the PV supply air temperature and flow rate do affect the local air quality. The PV system coupled with DV system can have a reduction of pollutant's exposure of up to 86% at the nose level when the polluting source is on the table as compared to DV only.