Roof geometry as a factor of thermal behavior: Simulation based study of using vaults and domes in the Middle East zone

Abstract

Vaults and domes were used as a roofing system and have been developed through time to mitigate the increasing structural, functional and climatic challenges. The evolutions in simulation programs open new research works and projects that study old domed/vaulted buildings practice and also what new constructed buildings designs should be. The significant climatic challenge of the selected region is hot temperature, so the thermal performance of building envelope specially the roofs is an important theme to be discussed. In this research, 14 roof cases between vaults, domes and double domes in five different arch-bases are proposed and thermally examined in three different cities represent three climatic conditions through the Middle East zone which are Cairo, Riyadh and Istanbul. The study depends on Autodesk Simulation CFD that could calculate the solar heating influence with consideration of natural distribution of heat flux and heat transfer. From comparing total heat flux, heat flux per proposed surface area unit and heat flux per horizontal surface area unit of all examined cases, the study finds that the pointed double domes roof is an effective one according to Cairo and Riyadh climatic conditions, while under Istanbul climatic conditions cases of half-circular/pointed domes and vaults have convergent results.