城市街道峡谷机动车排放氮氧化物扩散模拟

Simulation of NOx Contaminative Gas Diffusion in the Street Canyon

为了研究风速、风向、环境温度、污染源以及建筑物距离等因素对街道峡谷中汽车排放污染物扩散影响特性,本文采用RNGk-ε湍流模型方程及污染物对流扩散方程对其进行了二维数值模拟,得到了街道峡谷中机动车排放氮氧化物的流场和浓度场,从而证明了风速、风向、环境温度、污染源与建筑物距离等因素对街道峡谷中汽车排放污染物扩散确有明显影响作用。

The given paper aims to introduce the author＇s investigation of the automobile＇s contaminative gas diffusion caused by the wind speed, wind orientation, temperature, distance of the contaminative fountain and buildings in the street canyon in thickly populated urban areas. The investigation was done with a 2D numerical simulation of flow where the distribution of the airflow and the concentration of the contaminative gas were collected and analyzed using the RNG k-ε turbulence model and the gas diffusion equation. The results show that wind speed, wind orientation, temperature, distance of thecontaminative fountain and buildings were all important to the pollutant dispersion of the urban street canyon.