Paper 1
The Influence of Evenly Distributed
Ceiling Mounted Personalized Ventilation Devices on the Indoor Environment
Yang Bin and S.C. Sekhar
Department of Building, School of Design and
Environment,
National University of Singapore, 4 Architecture
Drive, 117566 Singapore
Abstract
The advantage of conventional personalized ventilation (PV) is to
considerably improve the fresh air percentage near PV air terminal devices
(ATDs). However, the distribution of the fresh air percentage is very
uneven in the field. Occupants are confined to their working zones in
order to obtain good inhaled air quality. Ceiling mounted PV can overcome
the disadvantages of conventional PV, although the fresh air percentage is
lower than that of conventional PV near working zones. A typical office
workplace consisting of either ceiling mounted PV ATDs or conventional PV
ATDs and ambient air supply diffusers is simulated, based on an indoor air
quality chamber at the National University of Singapore. Based on the
numerical results, it is concluded that ceiling mounted PV can improve
inhaled air quality for both seated occupants and moving occupants over a
longer occupied area although conventional PV can improve inhaled air
quality much better in the immediate breathing zones at the work stations.
Key words:
ceiling mounted personalized ventilation (PV), conventional
personalized ventilation, moving person, computational fluid dynamics (CFD),
dynamic mesh.
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