Air pollution dispersal in high density urban areas: Research on the triadic relation of wind, air pollution, and urban form. (March 2020)

• Record Type: Journal Article
• Authors: Yang, Junyan; Shi, Beixiang; Shi, Yi; Marvin, Simon; Zheng, Yi; Xia, Geyang
• Is Part Of: Sustainable cities and society. Volume 54(2020)
• Publication Date: 2020-03
• Subjects: Air pollution -- Urban form -- Wind environment -- High-density area; Sustainable urban development -- Periodicals; Sustainable buildings -- Periodicals; Urban ecology (Sociology) -- Periodicals; 307.76
• DOI: 10.1016/j.scs.2019.101941
• Languages: English
• ISSNs: 2210-6707

Abstract

Highlights: Propose the triadic relationship of urban form-ventilation-air pollution dissipate Simulate the air pollution flow in real urban 3D form condition Provide urban design optimization strategy for pollutant dissipate in multi-scale Abstract: Currently, urban air pollution becoming the major issue of urban physical environment in high density urban area. Many wind-calm zones or vortex zones can be formed where air pollution is retained or concentrated, which affects the environment and human health. To investigate this problem, the authors analyzed changes of wind velocity, direction, and air pollutant flow caused by changes in building height, volume, form, and density using a simulated three-dimensional (3D) conceptual model. The authors conducted an empirical study based on a representative high-density urban area. The results reveal that the actual 3D-simulated environment is complex. The wind environment changes continuously, and the retention or flow of the air pollutants changes drastically as well. The corner wind zones surrounding high-rise buildings may even generate new dust pollution due to the overly high wind speed. In this process, building height volume, layout, and orientation all significantly influence the flow and distribution of air pollution. Based on theoretical and empirical study, this paper discussed spatial planning strategies on the macroscopic city level, mesoscopic block level, and microscopic building level intended to promote the rapid dispersion of air pollutants by controlling the wind environment through optimizing the urban form.