PERFORMANCE OF PERSONALIZED VENTILATION SYSTEM IN CONJUNCTION WITH A PERSONALIZED EXHAUST DEVICE

Abstract

This dissertation focuses on the performance of a Personalised Ventilation (PV) system in conjunction with a Personalised Exhaust (PE) device. The aim of this research is to evaluate the effectiveness of the PE device in providing a better inhaled air quality within the breathing zone of the occupants. Literature reviews on PV system were done to gain a deeper understanding of its function and the various factors affecting its performance. Although the PV system is effective in delivering better inhaled air quality to the occupants, there remains a risk of the direct fresh air intake will be contaminated with the room air before inhalation by the occupants. Therefore, literature reviews were also done on personalized exhaust devices to explore the possibility of eliminating contamination of the fresh air with the room air. A workstation with manikin was set up to simulate office conditions. PV and PE systems, coupled with background ventilation systems were in place to facilitate the collection of primary data. The experiment was conducted with different conditions of varying distances, angles, PV flow rates and PE flow rates to simulate a range of movement area of the occupant. Each set of conditions were conducted once each for both Mixing Ventilation (MV) and Displacement Ventilation (DV) as the background ventilation. The Personalised Exposure Effectiveness (PEE) index was used to assess the amount of personalised air inhaled under these different conditions. The results obtained indicated that the amount of personalized air inhaled showed positive correlation with PV and PE flow rates and negative correlation with distance and angles. Varying angles were also found to have the greatest extent of influence on the amount of personalised air inhaled. From all the experimental set of conditions, the ideal condition whereby the optimal amount of personalised air inhaled was identified to be 20cm/0°/DV regardless of PV and PE flow rates. Limitations were identified to illustrate that PEE alone may not be a comprehensive indicator of the performance of the PV system. The conclusion of this research study showed that the addition of PE devices indeed enhances the PV system by increasing the amount of personalised air inhaled.