Thermal study of domed roofs in a traditional bazaar (the case of old Ganj-Alikhan bazaar in Kerman, Iran)

Abstract

The impact of dome shaped roofs of various buildings on thermal comfort has been investigated by many researchers across the world. However, thus far, the advantage (or disadvantage) of multiple-domed roofs, which are most common in ancient bazaars of Iran, has not been evaluated. The subject of this article is to study the effect of shadows of multi-domed roofs on the receiving solar radiation on their surface temperature variation during a summer day. For studying, a numerical program for 3D geometry and quasi-steady state heat transfer is developed. The code is used to calculate and compare receiving solar radiation and temperature distribution on the dome roof as well as for flat roof in a hot summer day. Besides, effect of domes' orientation (north-south & east-west) and the ratio of height to radius of dome on the shadow area are determined during the day time. To validate the code, temperature distribution on the roof of numerical solution is compared with thermo-graphical pictures taken experimentally from Kerman's historical bazaar (for the same condition). The results show that despite the positive effect of using multiple-domed roofs on producing shadows, total heat transfer from roof is more in comparison with flat roofs. However, most part of the transferred heat is able to be convected out through the top opening of the dome.