柴油卡车实际道路氮氧化物排放特征分析

利用SEMTECH-DS车载排放分析仪对3辆柴油卡车进行实际道路排放测试,获得了车辆的行驶工况、油耗及污染物排放数据,并分析得到工况、油耗与NO_x、NO和NO_2排放之间的关系.结果表明:测试车辆NO_x排放与各行驶工况下的速度、加速度及油耗密切相关.速度对NO_x、NO、NO_2排放速率的影响主要体现在高速阶段,此阶段排放速率随速度的增加迅速升高,而NO_x排放因子在速度为40～60 km/h时达到最低;车辆行驶过程中当加速度大于-0.3 m/s~2时,NO_x、NO和NO_2排放速率和排放因子均随加速度的增加而升高,且随着速度段的提高,这种趋势愈加明显;当油耗速率在0.04～0.07 L/s时,NO_x、NO和NO_2排放速率随油耗增加基本不变,其排放因子则不断减小,说明合理控制油耗将有利于NO_x排放的减少.

STUDY OF ON-ROAD EMISSION CHARACTERISTICS OF NITROGEN OXIDES FROM DIESEL TRUCKS

On-road emission test were conducted on three diesel trucks by using SEMTECH-DS.Data of driving behavior,fuel consumptions and emissions were obtained.The relationships among driving behavior,fuel consumption and NO_x,NO,NO_2 emissions were analyzed.The results showed that the NO_x emission of tested vehicle was strongly related with its speed,acceleration and fuel consumption; Speed had great effects on NO_x,NO emission rates when it was in high speed phase.The NO_x emission factor during the speed of 40～60 km/h were lowest than the other driving pattern;The NO_x emission rate and emission factor were increased with the increasing acceleration when it was above- 0.3 m/s~2.With the increasing of speed phase,the tendency was more obvious.When fuel consumption was between 0.04 and 0.07 L/s,NO_x,NO,NO_2 emission rate kept stabile but the emission factors were decreased with fuel consumption.It can be figured out that if fuel consumption was on a rational area,NO_x emission could be decreased effectively.