The synergistic effect of street canyons and neighbourhood layout design on pedestrian-level thermal comfort in hot-humid area of China

The traditional shophouse neighbourhoods (TSNs) appropriately integrated multiple variables of urban morphology for enhancement of pedestrian-level thermal comfort (PTC) in hot and humid climate zones. Understanding the synergistic effect of these design variables in TSNs on PTC is helpful for urban planners and designers. This research developed a prototype parametric TSN model to investigate the synergistic effect of four main variables: neighbourhood layout configurations, canyon type (alley, arcade street, boulevard), canyon axis orientation and canyon aspect ratio (HW). The data from the in-situ measurements in a TSN of Guangzhou in summer were used as the boundary condition for simulation in ENVI-met V4.3 and validation on the results. The Physiological Equivalent Temperature was adopted to assess PTC in different cases generated by the prototype parametric TSN model. The main findings are as follows: a) both arcade and greening had significant cooling efficiency for pedestrians, especially in East-West oriented streets; b) only the PTC in alleys was sensitive to all design variables; c) favourable PTC was shown in the neighbourhood with long East-West oriented arcade streets and that in square block layout with alleys; and d) the PTC in all boulevards dramatically responded only to HWs higher than 0.67.