Paper 8: Volume 4 No.4 March 2006 Edition
Verification
of Design Calculations of a Wind Catcher/Tower Natural Ventilation System
with Performance Testing in a
Real
Building
Abbas
Ali Elmualim
Innovative
Construction Research Centre, The
School
of
Construction
Management and Engineering,
The
University
of
Reading
, Whiteknights,
Reading
,
RG6 6AW
,
UK
Abstract
A
wind catcher/tower natural ventilation system was installed in a seminar
room in the building of the
School
of
Construction Management
and Engineering, the
University
of
Reading
in the
UK
. Performance was analysed by means of ventilation tracer gas
measurements, indoor climate measurements (temperature, humidity, CO2)
and occupant surveys. In addition, the potential of simple design tools
was evaluated by comparing observed ventilation results with those
predicted by an explicit ventilation model and the AIDA implicit
ventilation model. To support this analysis, external climate parameters
(wind speed and direction, solar radiation, external temperature and
humidity) were also monitored. The results showed the chosen ventilation
design provided a substantially greater ventilation rate than an
equivalent area of openable window. Also air quality parameters stayed
within accepted norms while occupants expressed general satisfaction with
the system and with comfort conditions. Night cooling was maximised by
using the system in combination with openable windows. Comparisons of
calculations with ventilation rate measurements showed that while AIDA
gave reasonably correlated results with the monitored performance results,
the widely used industry explicit model was found to over estimate the
monitored ventilation rate.
Key
words: natural
ventilation, wind catcher, calculations, comparisons with measurements,
tracer gas, air quality parameters, occupant assessment, thermal comfort,
passive cooling, case study.
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|
IJV Volume 4 No 4
Contents
Paper
1: Interacting Plumes
Paper
2: Outlet C-Values
Paper
3: Wind Driven Flow
Paper
4: CFD & Full-Scale
Paper
5: Tomography
Paper
6: Time Varying
Paper
7: Pre - Cooling
Paper
8: Wind Catcher
|
