Study On The Distribution Of Traffic Pollutants In Urban High Density Blocks

China is facing the unprecedented high-speed urbanization process.City is developing continuously,with the higher intensity of construction and increasing building capacity.The construction of severe urbanization has raised people's living standard to a certain extent,and has brought a series of environmental problems at the same time.With the development of city,the amount of vehicle is rising.Especially in the big city like Shenzhen,traffic is the main source of air pollution of the city.The increase of building density hindered city ventilation,air pollution caused by traffic is difficult to spread or gathered in the city environment.That leads the city air pollution problems becoming more and more serious."Haze" phenomenon frequent.With the increasing density of human living,human becoming more sensitivity to the urban environment,and the requirement to solve environmental problems is also becoming more and more urgent.In the face of environmental pressure,it is necessary to study the distribution of pollutants in the urban environment in order to improve the quality of the environment.According to the relevant research at home and abroad,the structure of the building and the layout of the building group will have a certain effect on the spatial distribution of air pollutants.Therefore,based on the perspective of regional planning and architectural design,this study focuses on the numerical simulation of pollutant ring in high-density city,the relationship between pollutant distribution and architectural form,and the improvement suggestions for planning and design.Based on the basic method of CFD simulation,we build suitable space models and grids,and establish reasonable turbulence models and boundary conditions according to the existing guiding principles.The pollution parameters of actual cases are simulated by MOVES software based on traffic volume,vehicle speed,vehicle emission ratio and road slope.Then the research objects were divided into raster,and the morphological elements in each grid were counted by GIS.The relationship between concentration and morphological elements was analyzed by SPSS software,and the multiple linear regression equation with concentration as dependent variable was obtained.In order to study the relationship between the spatial distribution of urban space and the spatial distribution of pollutants,7 groups of abstract models with the same strength of construction are designed and simulated.By comparing the concentration results,the local vector distribution and the vertical distribution of concentration in the front and rear fields of the layout,we conclude the influence of the architectural form and the layout of the building on the spatial distribution of pollutants.The main purpose of this study is to analyze the simulation results of real cases and abstract models,and drawing the law of pollutant distribution in urban high-density neighborhoods.According to the rule of summarizing,we get the optimization strategy of actual planning and architectural design,and provide reference for future project planning and architectural design,so as to improve the atmospheric environment quality of pedestrian street in urban high-density neighborhoods.