重型柴油车是我国目前最主要的交通工具,并占据了较高的NOx和PM排放,基于实际道路行驶测量方法(PEMS)模拟后处理中毒和老化情况下的实车排放,选取了一辆技术路线为:EGR + DOC + DPF + SCR的国六重型柴油车进行不同劣化件组合的排放分析。结果表明:DOC失效比SCR转化效率降低产生的NOx排放更多;低速行驶时,EGR率过高反而会导致排放增加;目前国六的技术路线能够很大程度上起到净化排气的作用;任何一个部件的异常工作状态都会导致排放明显增加。Heavy duty diesel vehicles are currently the most important means of transportation in China, accounting for a high proportion of NOx and PM emissions. Based on the actual road driving measurement method (PEMS) simulation of post treatment emissions under poisoning and aging conditions, a national VI heavy duty diesel vehicle with a technical route of EGR + DOC + DPF + SCR was selected for emission analysis of different deteriorated component combinations. The results show that DOC failure produces more NOx emissions than SCR conversion efficiency reduction;When driving at low speeds, an excessively high EGR rate can actually lead to an increase in emissions;At present, the technical route of National VI can largely play a role in purifying exhaust gas;The abnormal working state of any component will lead to a significant increase in emissions.
