关键词: 街道空间布局, 风环境模拟, 街道贴线率, 街道界面密度, 街道高宽比

Abstract:

With a rapid urbanization in Asia, the high-density new urban-center districts have already changed the microclimate in the city. Because of the using characters of building, the commercial streets which have emerged massively making a large number of pedestrians appear, pedestrian comfort in the commercial streets of the new urban-center districts requires more attention. Different street spatial layout will lead to change the internal wind environment in it and then affect the pedestrian comfort. Computational fluid dynamics (CFD) models are used to study the correlation between the three main street spatial layout factors, which are near-line rate, street interface density and street aspect ratio, under the simulation of relevant weather conditions. The results are mainly the following three points, first, the wind speed within the street change with the increase in the near-line rate like a parabola trend, and the wind speed reaches its peak about at a near-line rate of 70%. In that cases, it’s conducive to ventilation. Second, as the street interface density decreases, the variation of the wind speed of each measuring point in the city streets is getting bigger and bigger, and then the pedestrian walking in it will feel a strong wind speed change and the comfort is greatly reduced. Thirdly, the wind speed in the city streets is inversely proportional to the street aspect ratio. These conclusions will provide an important reference and evaluation basis for urban designers at the beginning of the design to effectively avoid future wind environmental problems.

Key words: street spatial layout, wind environment, near-line rate, street interface density, street aspect ratio