Seasonal Changing Effect on Airflow and Pollutant Dispersion Characteristics in Urban Street Canyons
In this study, the effect of seasonal variation on air flow and pollutant dispersion characteristics was numerically investigated. A three-dimensional urban canopy model with unit aspect ratio (H/D = 1) was used to calculate surface temperature distribution in the street canyon. Four representative...
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| Format: | Article |
| Language: | English |
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MDPI AG
2017-02-01
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| Series: | Atmosphere |
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| Online Access: | http://www.mdpi.com/2073-4433/8/3/43 |
| _version_ | 1818276784224862208 |
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| author | Jingliang Dong Zijing Tan Yimin Xiao Jiyuan Tu |
| author_facet | Jingliang Dong Zijing Tan Yimin Xiao Jiyuan Tu |
| author_sort | Jingliang Dong |
| collection | DOAJ |
| description | In this study, the effect of seasonal variation on air flow and pollutant dispersion characteristics was numerically investigated. A three-dimensional urban canopy model with unit aspect ratio (H/D = 1) was used to calculate surface temperature distribution in the street canyon. Four representative time events (1000 LST, 1300 LST, 1600 LST and 2000 LST) during typical clear summer and winter days were selected to examine the air flow diurnal variation. The results revealed the seasonal variation significantly altered the street canyon microclimate. Compared with the street canyon surface temperature distribution in summer, the winter case showed a more evenly distributed surface temperature. In addition, the summer case showed greater daily temperature fluctuation than that of the winter case. Consequently, distinct pollutant dispersion patterns were observed between summer and winter scenarios, especially for the afternoon (1600 LST) and night (2000 LST) events. Among all studied time events, the pollutant removal performance of the morning (1000 LST) and the night (2000 LST) events were more sensitive to the seasonal variation. Lastly, limited natural ventilation performance was found during the summer morning and the winter night, which induced relatively high pollutant concentration along the pedestrian height level. |
| first_indexed | 2024-12-12T22:51:09Z |
| format | Article |
| id | doaj.art-242dcc6ab5c240acaf80011b5c09c95f |
| institution | Directory Open Access Journal |
| issn | 2073-4433 |
| language | English |
| last_indexed | 2024-12-12T22:51:09Z |
| publishDate | 2017-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Atmosphere |
| spelling | doaj.art-242dcc6ab5c240acaf80011b5c09c95f2022-12-22T00:09:04ZengMDPI AGAtmosphere2073-44332017-02-01834310.3390/atmos8030043atmos8030043Seasonal Changing Effect on Airflow and Pollutant Dispersion Characteristics in Urban Street CanyonsJingliang Dong0Zijing Tan1Yimin Xiao2Jiyuan Tu3College of Urban Construction and Environmental Engineering, Chongqing University, Chongqing 400030, ChinaCollege of Urban Construction and Environmental Engineering, Chongqing University, Chongqing 400030, ChinaCollege of Urban Construction and Environmental Engineering, Chongqing University, Chongqing 400030, ChinaSchool of Engineering, RMIT University, Bundoora, VIC 3083, AustraliaIn this study, the effect of seasonal variation on air flow and pollutant dispersion characteristics was numerically investigated. A three-dimensional urban canopy model with unit aspect ratio (H/D = 1) was used to calculate surface temperature distribution in the street canyon. Four representative time events (1000 LST, 1300 LST, 1600 LST and 2000 LST) during typical clear summer and winter days were selected to examine the air flow diurnal variation. The results revealed the seasonal variation significantly altered the street canyon microclimate. Compared with the street canyon surface temperature distribution in summer, the winter case showed a more evenly distributed surface temperature. In addition, the summer case showed greater daily temperature fluctuation than that of the winter case. Consequently, distinct pollutant dispersion patterns were observed between summer and winter scenarios, especially for the afternoon (1600 LST) and night (2000 LST) events. Among all studied time events, the pollutant removal performance of the morning (1000 LST) and the night (2000 LST) events were more sensitive to the seasonal variation. Lastly, limited natural ventilation performance was found during the summer morning and the winter night, which induced relatively high pollutant concentration along the pedestrian height level.http://www.mdpi.com/2073-4433/8/3/43street canyonseasonal variationair flowpollutant dispersionpollutant removalnatural ventilation |
| spellingShingle | Jingliang Dong Zijing Tan Yimin Xiao Jiyuan Tu Seasonal Changing Effect on Airflow and Pollutant Dispersion Characteristics in Urban Street Canyons Atmosphere street canyon seasonal variation air flow pollutant dispersion pollutant removal natural ventilation |
| title | Seasonal Changing Effect on Airflow and Pollutant Dispersion Characteristics in Urban Street Canyons |
| title_full | Seasonal Changing Effect on Airflow and Pollutant Dispersion Characteristics in Urban Street Canyons |
| title_fullStr | Seasonal Changing Effect on Airflow and Pollutant Dispersion Characteristics in Urban Street Canyons |
| title_full_unstemmed | Seasonal Changing Effect on Airflow and Pollutant Dispersion Characteristics in Urban Street Canyons |
| title_short | Seasonal Changing Effect on Airflow and Pollutant Dispersion Characteristics in Urban Street Canyons |
| title_sort | seasonal changing effect on airflow and pollutant dispersion characteristics in urban street canyons |
| topic | street canyon seasonal variation air flow pollutant dispersion pollutant removal natural ventilation |
| url | http://www.mdpi.com/2073-4433/8/3/43 |
| work_keys_str_mv | AT jingliangdong seasonalchangingeffectonairflowandpollutantdispersioncharacteristicsinurbanstreetcanyons AT zijingtan seasonalchangingeffectonairflowandpollutantdispersioncharacteristicsinurbanstreetcanyons AT yiminxiao seasonalchangingeffectonairflowandpollutantdispersioncharacteristicsinurbanstreetcanyons AT jiyuantu seasonalchangingeffectonairflowandpollutantdispersioncharacteristicsinurbanstreetcanyons |