Solar-Wind Generated Roof Ventilation System (SiVATAS)
for a
Warm-Humid Climate
Prasasto
Satwiko
School of
Architecture, University of Atma Jaya Yogyakarta,
Jl. Babarsari 44 Yogyakarta 55281, Indonesia
Abstract
This research grows out of
a desire to find a Solar-Wind Generated Roof Ventilation System for
low-cost dwellings located in high building density urban areas where
horizontal air movement is restricted. A general purpose computational
fluid dynamics (CFD-ACE+) program was utilised to explore, analyse and
develop a roof model based on its aerodynamics and thermal performance to
obtain optimum wind pressure and temperature differences. Comparisons
were made with physical scale models. The research found that a
roof prototype with inclinations of 15o and 45o,
curved ridge with cap, integrated roof chimney, black-matte steel sheet
cover, combined with a perforated under floor channel (floor tunnel), can
generate evenly distributed vertical cross ventilation within the
occupant’s zone. The created indoor air velocity was in the range of
0.15 to 0.7 m/s, which is considered to be sufficient to produce a
physiological cooling effect. As an addition, the CFD program has proved
to be a reliable, user-friendly and helpful research tool.
Key words: natural
ventilation, solar chimney, CFD modelling, physiological cooling, humid
climate, physical model, roof configuration, indoor air velocity, physical
scale models.
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