Paper 5: Volume 5 No.3 Dec 2006 Edition
Air Quality and Thermal Comfort
in an Office with Underfloor, Mixing and Displacement Ventilation
R Cermak1
and AK Melikov2
1Ingersoll
Rand Climate Control Technologies, R&D Centre
Prague
, CZ-25301
Hostivice
,
Czech Republic
2International
Centre for Indoor Environment and Energy, Department of Mechanical
Engineering,
Technical
University
of
Denmark
, Building 402, DK-2800
Lyngby
,
Denmark
Abstract
An underfloor ventilation
system providing three different airflow patterns, a mixing ventilation
system, and a displacement ventilation system utilizing a wall-based
diffuser were tested in a mock-up of a typical office. The systems were
operated under identical conditions. The criteria for evaluation included
the distribution of air exhaled by two breathing thermal manikins,
pollution emitted from the floor covering, velocity and temperature. It
was shown that the inhaled air quality in rooms with underfloor
ventilation depends on the association between the vertical penetration
height of supply airflows and the stratification height of exhaled
pollutants. However, no difference between the ventilation systems was
found in regard to the floor pollution. The main conclusion is that
underfloor ventilation systems providing a short vertical throw can ensure
both a high air quality and a lower risk of thermal discomfort as compared
to displacement ventilation and underfloor ventilation with a horizontal
discharge pattern.
Key words: air quality,
thermal comfort, air distribution, underfloor ventilation.
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Contents
Editorial
Ventilation
for Better Indoor Air Quality: Yuguo
Li
and Xianting
Li
Paper 1
Ventilation
for Better Indoor Air Quality: Yuguo
Li
and Xianting
Li
Paper
2
Performance
of Underfloor Air Distribution in a Field Setting: Fisk, W. J., Faulkner,
D., Sullivan, D. P., Chao, C., Wan, M. P., Zagreus, L. and Webster, T.
Paper 3
Applying
the Local Dynamic Similarity Model and CFD for the Study of
Cross-Ventilation: Hu, C-H.,
Kurabuchi, T. and Ohba, M.
Paper
4
Levels
of Indoor Airborne Microbes Associated with Ventilation Efficiency in
Naturally-Ventilated Residences: Su, H. J., Wu, P. C. and Chien, H. P.
Paper 5
Air
Quality and Thermal Comfort in an Office with Underfloor, Mixing and
Displacement Ventilation:
Cermak, R. and Melikov, A. K.
Paper
6
Passive
Tracer Gas Measurement of the Long Term Variation of Ventilation in Three
Swedish Dwellings: Stymne, H., Emenius, G. and Boman, C. A.
Paper
7
Validation
of a CFD Model for Research into Stratum Ventilation: Lin,
Z., Chow, T. T. and Tsang, C.F.
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