街道峡谷形态对污染物扩散的数值模拟  

Numerical Simulation of the Effect of Street Canyon Shape on Pollutant Dispersion

作　　者：雷林清 崔鹏义 黄远东[1] LEI Linqing;CUI Pengyi;HUANG Yuandong(School of Environment and Architecture,University of Shanghai for Science and Technology,Shanghai 200093,Chin)

机构地区：[1]上海理工大学环境与建筑学院,上海200093

出　　处：《上海理工大学学报》2018年第3期282-289,共8页Journal of University of Shanghai For Science and Technology

基　　金：国家自然科学基金资助项目(51536006)

摘　　要：机动车排放的尾气污染物,在城市街道峡谷内的稀释扩散及分布特性,主要由街道内流动结构决定,而街道布局和结构对流动结构有重要影响。基于二维不可压缩流动的Navier-Stocks方程、污染物组分输运方程及标准k-?湍流模型,获取所构建模型的数值解。采用验证的模型参数,构建了9种2类高宽比H/W为1的二维城市街道截面形态构造,在来流平均风速为3 m/s情况下,研究了街道截面形态对机动车尾气污染物扩散传递的影响。结果表明:下沉式道路结构不会改变街道峡谷内主涡结构和污染物分布;随着下沉深度的增加,机动车道内污染程度将进一步加剧;廊道内污染物浓度分布受廊道高度的影响较大,其人行呼吸高度处背风侧附近污染物浓度值相对参考工况增加大约5%,廊道深度对街谷内污染物扩散影响不大。The dispersion and distribution characteristics of the exhaust pollutants emitted by motor vehicles in the urban street canyons are mainly determined by the air flow structures, and there exists an important influence for the street layouts and configurations on the air flow structures. Based on solving the Navier-Stocks equation, the transport equation of the pollutant component and the standard k-？turbulence model for 2 D incompressible flow, the numerical solutions were obtained. Nine kinds of cross-section shapes of urban street canyons（two types） were constructed to study the effect on the pollutant dispersion within urban street canyons under 3 m/s for the inlet profile. The results show that the main vortex structure and pollutant distributions in the street canyon won＇t change due to the sinking of the vehicle lane. However, the pollution level in the motorway will increase as the sinking depth increases. In addition, the concentration distribution of pollutants in the corridor was greatly influenced by the height of the corridor. The average pollutant concentration on the respiratory plane near the leeward side increased by about 5% compared to the reference case（case 1）. The corridor depth has little effect on pollutant dispersion in street canyon.

关 键 词：城市街道峡谷 街道峡谷形态 污染物扩散 数值模拟 

分 类 号：X169[环境科学与工程—环境科学]