Evaporatively-cooled window driven by solar chimney to improve energy efficiency and thermal comfort in dry desert climate

This study investigates the performance of an evaporatively-cooled window driven by solar chimney attached to external façades for providing acceptable thermal comfort at low energy consumption in an office space. A validated simplified model of the novel system was coupled with a developed 3-D computational fluid dynamics (CFD) model of the office space to predict the space window outer surface temperature. The CFD model was then coupled with a validated bio-heat model that was integrated with Zhang model to predict local and overall thermal sensation and comfort. Two representative hours were selected mainly 14 h and 17 h for hot and dry climate conditions for a space located in Riyadh. The reported results showed significant improvement in overall thermal comfort when the novel system is used to reach a thermal comfort level of 1.42 at 14 h and 1.96 at 17 h using a comfort scale varying from very uncomfortable at −4 to very comfortable at +4. Energy savings reaching 10% were recorded during both hours.