Paper 7
Solar Chimney Geometry for Stack
Ventilation in a Warm Humid Climate
Agung Murti Nugroho
Faculty of Engineering, Brawijaya University, Malang,
Indonesia
Abstract
Natural ventilation is a well known strategy to improve indoor air
velocity and reduce indoor temperature. It is the main criterion to
achieve thermal comfort in terraced housing in Malaysia. In hot and humid
climates, one drawback to single sided ventilation is that the wind effect
is not well captured, which in turn, increases the use of mechanical
cooling. Therefore, it is important to understand and consider the use of
the solar chimney as a stack induced ventilation strategy for a single
sided ventilated room. This study investigates solar chimney geometry to
improve indoor air velocity and to reduce temperature in order to achieve
comfort ventilation in hot and humid climates. An experiment was carried
out to measure the natural ventilation rate of a single master bedroom in
a typical single storey terrace house. The investigation was assisted
using FloVent 5.1, a computational fluid dynamic simulation program which
was first validated by comparing simulated results with field measurements
taken on site. The results of the experiment showed that an optimum solar
chimney geometry model of 3.5 m height, 3.5 m length and 1 m width gap
could increase the indoor air velocity by more than 30% when compared with
the standard field study model. This effect is significant towards
improving air velocity for thermal comfort performance in conventional
terraced housing through passive natural ventilation. In conclusion,
optimisation and modification of solar chimney geometry can further
improve the air velocity for increased ventilation and thermal comfort.
Key words: solar chimney geometry, stack ventilation,
ventilation for thermal comfort.
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