Numerical evaluation of thermal comfort in traditional courtyards to develop new microclimate design in a hot and dry climate

Abstract

The growing interest in thermal comfort of outdoor environments yields in different analysis on courtyards as a common space between urban and architectural scales. However, there is a limited knowledge regarding the microclimatic behavior of such spaces. Using ENVI-met simulations, this paper aims to numerically discuss the thermal performance of different configurations of traditionally designed courtyards in Shiraz, Iran, which experiences hot summers and cold winters. The geometrical effects such as orientation and H/W (height to width ratio) of courtyards are considered as potential parameters to improve the microclimatic conditions. In this paper, PMV and UTCI are used as thermal comfort indices.The obtained results indicate mean radiant temperature and wind speed as the most effective parameters for thermal comfort of courtyards. In addition, the aforementioned geometrical parameters might not be able to solely create a desirable condition, but they could significantly improve the thermal comfort of courtyards during summer and winter. To achieve a desirable thermal comfort level, the results suggest using configurations of a high H/W rate and southward orientation in order to obtain better shading during summer as well as allowing the solar radiation in while regulating the wind speed in winter.

Sustainable design of courtyard environment: From the perspectives of airborne diseases control and human health

“…Previous research optimized design of opening level of courtyards by CFD (Computational Fluid Dynamics) simulation and experimental measurement to improve natural ventilation performance in hot summer and cold winter (HSCW) climate zones ( Hao et al, 2019 ). To improve natural ventilation and thermal comfort in courtyards, courtyard layout, aspect ratio, height-width ratio and southward orientation were optimized by numerical simulations ( Nasrollahi, Hatami, Khastar, & Taleghani, 2017 ; Xu, Luo, Wang, Hong, & Fu, 2018 ). Similarly, the influences of opening angles/distributions, incoming wind orientations and courtyard height on ventilation performance and comfort level were also simulated by using CFD method ( Micallef, Buhagiar, & Borg, 2016 ; Mousa, Lang, & Auer, 2017 ; Subhashini & Thirumaran, 2019 ).…”

The role of sky view factor and urban street greenery in human thermal comfort and heat stress in a desert climate

“…Greenery is one of the most effective elements of a human-biometeorological oriented design which plays an important role in improving thermal comfort (Middel et al, 2015, Taleghani and Berardi, 2018, Lee and Mayer, 2018. There are many studies that showed the heat mitigation impacts of vegetation in traditional courtyards (Foruzanmehr and Vellinga, 2011, Nasrollahi et al, 2017, and in urban scale (Akbari andKolokotsa, 2016, Yan et al, 2018) in arid climates. Due to the water shortage in such climates, urban greenery needs to be designed in the most efficient way.…”

The Effect of Tree-Planting Patterns on the Microclimate within a Courtyard

“…Courtyards tend to be the primary outdoor spaces for recreational activities as well. As a result, landscape architects focus on improving thermal comfort within courtyards during hot summers and cold winters [13,14]. Courtyards with a southward orientation and configurations of high Height/Width can achieve a better thermal comfort level both by shading during summer and regulating the wind speed in winter [14,15].…”