国六重型车SCR系统不同劣化程度下的NO_(x)排放特征研究  

Research on NO_(x)Emission Characteristics of SCR System of NationalⅥHeavy-Duty Vehicles under Different Degrees of Deterioration

作　　者：覃昭翔 马成功 杨涛 李梁[2] Qin Zhao-xiang;Ma Cheng-gong;Yang Tao;Li Liang(Dongfeng Liuzhou Motor Co.,Ltd.,Guangxi Liuzhou 545005;China Automotive Technology and Research Center Co.,Ltd.,Beijing 300300,China)

机构地区：[1]东风柳州汽车有限公司,广西柳州545005 [2]中国汽车技术研究中心有限公司,北京100176

出　　处：《内燃机与配件》2025年第3期14-17,共4页Internal Combustion Engine & Parts

摘　　要：本研究通过对国六重型柴油车选择性催化还原(SCR)系统不同部件开展不同劣化程度的模拟,基于车载排放测试(PEMS)和底盘测功机油耗排放测试研究国六柴油车SCR系统在不同劣化程度下的氮氧化物(NO_(x))排放特征。结果表明,当SCR催化剂劣化后,NO_(x)排放显著增加,且随着劣化程度加重NO_(x)排放有升高的趋势。SCR催化剂在某些劣化程度下仍有可能出现排放超限而OBD系统未能有效识别并报警。SCR上游温度传感器劣化后,NO_(x)排放虽有增加,但当劣化到一定程度后,OBD系统能监测到信号失真并调整尿素喷射策略,使得NO_(x)排放始终控制在国六限值内。In this study,different components of the selective catalytic reduction(SCR)system of National-Ⅵdiesel vehicles were simulated with different degrees of deterioration,and the emission characteristics of nitrogen oxides(NO_(x))of the SCR system of National-Ⅵdiesel vehicles under different degrees of deterioration were studied based on on-board emission test(PEMS)and chassis dynamometer fuel consumption emission test.The results show that NO_(x)emission increases significantly after SCR catalyst degradation,and NO_(x)emission tends to increase with the deterioration degree.The SCR catalyst may still have emission limit under certain degree of degradation,and OBD system can not effectively identify and alarm.After the deterioration of the upstream temperature sensor of SCR,NO_(x)emissions increase,but when the deterioration to a certain extent,the OBD system can monitor the signal distortion and adjust the urea injection strategy,so that NO_(x)emissions are always controlled within the National-Ⅵlimit.

关 键 词：国六柴油车 SCR 排放特征 劣化程度 

分 类 号：TK421.5[动力工程及工程热物理—动力机械及工程]