低速汽车实际道路气态污染物排放特征

 利用SEMTECH-DS车载排放测试系统,对6辆典型低速汽车进行实际道路车载排放测试,获得测试车辆逐秒速度,CO₂,CO,NO_x和碳氢化合物(HC)等气态污染物排放数据.基于测试数据,对工况与污染物排放之间的关联进行解析,计算并分析了4种污染物的排放因子.结果显示,低速汽车CO₂,CO,NO_x和HC 4种污染物排放因子总体上随速度增加而下降,随加速度增加而升高;不同行驶下的排放速率:加速＞匀速＞减速＞怠速;各污染物排放速率与比功率(VSP)呈现很好的相关规律.测试低速汽车CO₂,CO,NO_x和HC平均排放因子分别为110.1,1.66,1.78和0.49g/km^-1,其中CO与国II轻型柴油车排放限值相当,NO_x和HC与国I轻型柴油车排放限值相当.

On-road Emission Characteristics of Gaseous Pollutants from Low-speed Vehicles

On-road emission tests were conducted for six low-speed vehicles using SEMTECH-DS, a Portable Emission Measurement System (PEMS). The instantaneous speed and emission concentration data of CO₂, CO, NO_x and HC were collected, and the relationship between the driving cycle and emission, and the emission factors are analyzed based on the testing data. The results show that the emission factors of CO₂, CO, NO_x and HC decrease with the increase of speed and increase with the increase of acceleration; the emission rates are the highest in the acceleration mode, followed by the cruising mode, and are the lowest in the idling mode. The emission rates of the four pollutants for low-speed vehicles have a very good correlation with VSP; the average emission factors of the CO₂, CO, NO_x and HC for tested low-speed vehicles are 110.1, 1.66, 1.78 and 0.49g·km^-1, respectively. The CO emission factors are comparable to the regulated values of light-duty diesel trucks with Nation II technology; and NO_x and HC emission factors are comparable to the regulated values of light-duty diesel trucks with Nation I technology.