怠速条件下汽车排气污染物在排气尾流中扩散特性的实验研究

通过实验的方法对怠速条件下汽车排气污染物在排气尾流中的扩散特性进行了研究.测定了怠速条件下汽车排气尾流中的污染物体积分数及其分布,并比较分析了3种不同类型汽车的污染物排放体积分数及其变化.实验结果表明,怠速时汽车排气尾流中的污染物体积分数按照近似指数函数的趋势迅速降低到接近大气背景值;不同类型汽车排气尾流中的污染物体积分数的差别非常明显;排气方向对汽车排放污染物的扩散及其分布具有重要的影响.研究工作可以为怠速工况下汽车排气污染物对周围环境的影响评价提供更多的有用信息.

Experimental study of the dispersion characteristics of vehicular pollutants in exhaust plume under idle condition

The dispersing characteristics of vehicular exhaust plume under idle condition is studied by using experimental method. Pollutant concentrations in the exhaust plume are measured and the comparison of pollutant concentration emitted from three different types of vehicles is made. The experimental results show that the concentrations of exhaust pollutants can be decreased exponentially close to the ambient concentration value rapidly, the difference of pollutant concentration for different types of vehicles is very obvious in the exhaust plume and tailpipe exit direction has important effect on the dispersion and distribution of vehicular exhaust pollutants in the exhaust plume when the vehicle operators under idle condition. It can provide much more information necessary for the evaluation of the effect of vehicle pollution emission on the environment when vehicles operate under idle condition.