Paper 8
Utility of Wind Catchers for Nocturnal Ventilation
Abbas
Ali Elmualim
Innovative
Construction Research Centre, School of Construction Management &
Engineering, The University of
Reading, RG6 6AW, United Kingdom.
Abstract
Wind catcher systems have
been employed in buildings in the Middle East for many centuries and they
are known by different names in different parts of the region. Recently
there has been an increase in the application of this approach for natural
ventilation and passive cooling in the UK and other countries. This paper
presents the results of experimental wind tunnel and smoke visualisation
testing, combined with CFD modelling, to investigate the performance of
the wind catcher. For this
purpose, a full-scale commercial system was connected to a test room and
positioned centrally in an open boundary wind tunnel. Because much
ventilation design involves the use of computational fluid dynamics, the
measured performance of the system was also compared against the results
of CFD analysis. Configurations
included both a heated and unheated space to determine the impact of
internal heat sources on airflow rate. Good comparisons between
measurement and CFD analysis were obtained. Measurements showed that
sufficient air change could be achieved to meet both air quality needs and
passive cooling.
Key words: natural
ventilation, night ventilation, passive cooling, wind catcher, wind
tunnel, CFD
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