干旱区生态环境知识资源中心

Due to rapid and intensified urbanisation in cities, the characteristics of outdoor urban microclimates have been detrimentally influenced, altering the perception and satisfaction of pedestrians, especially in hot and dry climates. This poses challenges to many researchers and urban space designers in finding appropriate methods to reduce the urban heat stress and thus to enhance the thermal comfort level of outdoor pedestrian spaces, to prolong the period of their use of space and viability as urban retreats. However, there is limited research conducted on outdoor urban spaces in hot arid climate. Therefore, the purpose of this current research is to review the outdoor thermal comfort interaction factors, as well as to contribute to the knowledge of the literature by conducting a case study of a pedestrian street in the hot dry city of Madinah, Saudi Arabia. It also aims to find out the available methods to increase the outdoor pedestrian thermal comfort level in hot and dry urban microclimates, in addition to understand how CFD simulation method can influence the urban space design and planning processes. This review covers the effect of the moderation of the built environment's components on the microclimatic parameters on pedestrians' scale, with the aim for optimising the thermal comfort level in outdoor urban spaces. The literature also covers the use of simulation tools used to simulate environmental conditions outdoors with specific focus on CFD simulation for outdoor thermal comfort applications. Finally, this paper expects to highlight the limitations of both the microclimatic enhancement approach and the CFD simulation as a tool in the field of urban design.