The evaluation of outdoor thermal sensation and outdoor energy efficiency of a commercial pedestrianized zone

Abstract

The growth of the scale of cities intensifies urban heat island (UHI) by obstructing the wind and building more radiation at pedestrian level, thus leading to an energy consumption. Commercial pedestrianized-zones cannot only become symbols of cities but also an important factor increasing local economic income. This study conducts on-site measurement and numerical simulation to evaluate the cooling energy efficiency of different parameters (building, vegetation, pavement material) in Fo Shan city, which locates in hot-summer and warm-winter climate region of China. Also, calculations are done to evaluate the index physiological equivalent temperature (PET) for understanding thermal sensation at a pedestrian level (1.5 m). To evaluate different impacts of this zone renewal on the environment and choose the most energy-saving method, it is easy for us to utilize the linear regression for understanding the relationship between coverage ratio of trees (TCR) and thermal comfort in canyon space, which shows that ∆PET = 0.1703 × TCR + 0.2444 with a most important R2 value of 0.9836, for TCR increases from 12.5% to 22%. In open space, also increasing coverage ratio of trees (TCR) can effectively improve humans' thermal comfort, which shows that ∆PET = 0.2644 × TCR + 0.3955 with a most important R2 value of 0.8892.