Experimental Study And Numerical Simulation Of Ultra-fine Particle Pollution In Hangzhou

Since the1980s, China has persisted in taking economic construction asthe core, making rapid economic development.At the same time, the environmentalissues become increasingly prominent as the focus of people’s attention. Streetcanyon is prevalent in urban spatial structure, and has a serious impact on the urbanwind field distribution and dispersion of pollutants. Experts and scholars at home andabroad, have done a large number of field measurements and numerical simulationon distribution and dispersion of CO and NO_x. However, the study of the distributioncharacteristics of particulate matter in the street canyon is not widespread.In this paper, the status quo and the main spatial and temporal characteristics ofparticulate matter pollution in Hangzhou city and suburbs study are studied, thecombination of meteorological factors on the distribution of diffusion of particlepollution in typical structure of street canyons are also analized. The study of particlepollution in Hangzhou is divided into two aspects, the experimental measurementsand numerical simulation, we introduce DUSTTRAKTMDRX8534dust monitor tomeasure fine and ultrafine particles mass concentration in Xihu District, GongshuDistrict, Jianggan District, Xiasha Economic Development zone and XiaoshanDistrict. We get a lot of monitoring data, from which we obtain the particle sizedistribution and statistical regularity under different spatial and temporal scales.FMPS3091(Fast Mobility Particle Sizer) are used to sample ultrafine particles of theLake District, Gongshu District, Xiasha Economic Development zone. We draw theparticle size spectrum, analyze the spatial and temporal differences in particle sizedistribution, and study meteorological factors, transport factors and other influencingfactors.In the area of numerical simulation, we apply computational fluid dynamics(CFD) software to simulate the air flow field and the law of the distribution ofparticulate matter in the typical two-dimensional street canyon and the complexitythree-dimensional street canyon.We select standard k-ε model to simulate continuousphase flow field, and the DPM model to describe the particle phase. The results showed that the simulation results and experimental data are consistent within theallowable error range.