Improving air quality in high-density cities by understanding the relationship between air pollutant dispersion and urban morphologies
Publication in refereed journal



摘要In high-density megacities, air pollution has a higher impact on public health than cities of lower population density. Apart from higher pollution emissions due to human activities in densely populated street canyons, stagnated air flow due to closely packed tall buildings means lower dispersion potential. The coupled result leads to frequent reports of high air pollution indexes at street-side stations in Hong Kong. High-density urban morphologies need to be carefully designed to lessen the ill effects of high density urban living. This study addresses the knowledge-gap between planning and design principles and air pollution dispersion potentials in high density cities. The air ventilation assessment for projects in high-density Hong Kong is advanced to include air pollutant dispersion issues. The methods in this study are CFD simulation and parametric study. The SST k-omega model is adopted after balancing the accuracy and computational cost in the comparative study. Urban-scale parametric studies are conducted to clarify the effects of urban permeability and building geometries on air pollution dispersion, for both the outdoor pedestrian environment and the indoor environment in the roadside buildings. Given the finite land resources in high-density cities and the numerous planning and design restrictions for development projects, the effectiveness of mitigation strategies is evaluated to optimize the benefits. A real urban case study is finally conducted to demonstrate that the suggested design principles from the parametric study are feasible in the practical high density urban design. (C) 2013 Elsevier Ltd. All rights reserved.
著者Yuan C, Ng E, Norford LK
期刊名稱Building and Environment
頁次245 - 258
關鍵詞Air pollution dispersion; Building geometry; CFD simulation; High-density urban design; Urban permeability
Web of Science 學科類別Construction & Building Technology; CONSTRUCTION & BUILDING TECHNOLOGY; Engineering; Engineering, Civil; ENGINEERING, CIVIL; Engineering, Environmental; ENGINEERING, ENVIRONMENTAL

上次更新時間 2020-20-11 於 01:06