Effects of Heat Intensity and Inflow Wind on the Reactive Pollution Dispersion in Urban Street Canyon

doi:10.1007/s12204-018-2030-x

Abstract

Abstract: This paper investigates the impacts of heating intensity and inflow wind speed on the characteristics of reactive pollutant dispersion in street canyons using the computational fluid dynamic (CFD) model that includes the transportation of NO, NO2, and O3 coupled with NO-NO2-O3 photochemistry. The results indicated that the heat intensity and inflow wind speed have a significant influence on the flow field, temperature field and the characteristics of reactive pollutant dispersion in and above the street canyon. With the street canyon bottom heating intensity increasing, NO, NO2 and O3 concentrations in street canyon are decreased. The O3 concentration reductions are even more than the NO and NO2 concentrations. Improving the inflow wind speed can significantly reduce the NO and NO2 concentrations within street canyons. But the O3 concentrations have a slight rise with wind speed increasing. The results would be useful for understanding the interrelation among reactive vehicle emissions, and provide references for urban planners.

Key words: reactive pollutant| dispersion| street canyon| heat intensity| inflow wind

摘要： This paper investigates the impacts of heating intensity and inflow wind speed on the characteristics of reactive pollutant dispersion in street canyons using the computational fluid dynamic (CFD) model that includes the transportation of NO, NO2, and O3 coupled with NO-NO2-O3 photochemistry. The results indicated that the heat intensity and inflow wind speed have a significant influence on the flow field, temperature field and the characteristics of reactive pollutant dispersion in and above the street canyon. With the street canyon bottom heating intensity increasing, NO, NO2 and O3 concentrations in street canyon are decreased. The O3 concentration reductions are even more than the NO and NO2 concentrations. Improving the inflow wind speed can significantly reduce the NO and NO2 concentrations within street canyons. But the O3 concentrations have a slight rise with wind speed increasing. The results would be useful for understanding the interrelation among reactive vehicle emissions, and provide references for urban planners.

关键词: reactive pollutant| dispersion| street canyon| heat intensity| inflow wind

CLC Number:

X 515

XIE Xiaomin (谢晓敏), ZHU Zhongwei (朱中伟). Effects of Heat Intensity and Inflow Wind on the Reactive Pollution Dispersion in Urban Street Canyon[J]. Journal of Shanghai Jiao Tong University (Science), 2018, 23(Sup. 1): 109-116.

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