Achieving Effective Thermal Performance of Street Canyons in Various Climatic Zones

Abstract

Outdoor thermal comfort is one of the essential characteristics of effective urban planning. The aspect ratio and orientation of the street canyon influence the thermal performance. Regulations standardize construction rules without accounting for regional climatic variations or the effect of these limits on pedestrian thermal comfort. The purpose of this paper is to provide an understanding of the effects of aspect ratios and street canyon orientations on thermal comfort in Alexandria, representing the North Coast Region of Egypt, and Aswan, representing the Southern Egypt Region, using ENVI-met and RayMan software for various aspect ratios and street canyon orientations scenarios. As a result, the aspect ratio (AR = 2.5) gives the best thermal conditions in all the scenarios evaluated in both cities, whereas the aspect ratio (AR = 1) provides the worst. Despite having the highest PET value among the investigated scenarios, the Northeast-Southwest street canyon in Aswan City has the least uncomfortable thermal hours. The North-South street canyon in Alexandria City has the best thermal performance, followed by the Northwest-Southeast street canyon. Finally, it was shown that the aspect ratio and the orientation of the street canyons in the North Coast and Southern Egypt regions can support pedestrian thermal comfort.