街谷几何形态及绿化对夏季热环境的影响

Effects of Street Geometry and Greening on Thermal Environment in Street Canyon in Summer

本文利用基于CTTC模型的DUTE软件,以湿热地区广州的城市街谷为例,对城市街谷内的湿球黑球温度(WBGT)和热岛强度进行了模拟计算。通过对比分析,比较了不同高宽比、走向、对称性、绿化等设计因素对街谷内日间平均WBGT和热岛强度的影响。研究结果表明:窄街谷较之宽街谷、南北走向街谷较之东西走向街谷有着更好的热环境;街谷乔木率与热岛强度的降低呈线性正相关;对称与否对街谷内热环境的影响较小。本文初步探索了街谷几何形态及绿化对街谷热环境的定量影响,为城市规划和街谷设计提供了有针对性的参考指引,以期促进街谷热环境的设计,营造安全、舒适的街谷热环境。

In this paper,using the software of DUTE, the parameters of WBGT and UHI intensity in Guangzhou street canyon with hot and humid climate were simulated, and the influence factors were discussed, including the ratio of height to width, street orientation, asymmetry and greening. The results demonstrated that the thermal environment in narrow canyon was better than that in wide canyon,and S-N canyon was better than E-W canyon. Furthermore,there was a positive liner correlation between the proportion of trees in the canyon and the decrease of UHI intensity. In addition, asymmetry had little impact on diurnal thermal environment of the canyon. This paper was a preliminary and quantitative study, which could provide references for urban planning and street canyon design.