摘要
应用数学建模方法对西安市空气中PM2.5的发生和演变进行合理性评估,对于建立城市污染物风险评估有着重要价值。本文应用地面连续点源扩散微分方程。对固定强度点源,在一定风速、温湿度条件下,湍流运动进行模拟后得到微分方程以及连续点源恒定条件下解析解。在水平风向平均风速为2.5m/s的条件下持续进行两小时,污染物浓度分布急剧下降,扩散效果最好且污染的扩散随风向呈椭圆形分布。
Mathematical modeling method is used for reasonable evaluation for the occurrence and evolution of PM2.5 in the air in Xi′an City. It is important for establishing urban pollutants risk evaluation. The ground continuous point source diffusion differential equation is applied in this article. After the simulation of the turbulent motion of fixed strength point sources under the condition of a certain windspeed, temperature and humidity, the differential equation is obtained, and theanalytic solution under the condition of constant continuous point source isalso obtained. When it lasts 2 hours under the condition that the averagehorizontal wind speed is 2.5m/s, there is a sharp drop in pollutant concentration distribution. The diffusion effect is the best and pollution diffusion comes into oval distribution with the wind direction.
出处
《价值工程》
2015年第27期196-199,共4页
Value Engineering
