我国典型进口轻型柴油车型NOx排放特性研究

摘要

介绍了当前轻型柴油车NOx排放的主要控制技术路线,并选取我国市场上典型进口轻型柴油车型进行NOx排放测试,对中规、欧规及美规不同技术路线的车型进行了NOx排放瞬态分析,并选择一辆采用SCR技术的美规车进行了冷、热起动对比试验.结果表明,当前我国市场上轻型柴油车型NOx排放呈现美规车＜欧规车＜中规车的基本形态,采用SCR技术的美规车工况覆盖性最好,采用EGR的欧规车通过优化燃烧可以达到欧五水平.冷起动是采用SCR技术的美规车产生NOx的主要原因,加速小负荷是轻型柴油车产生NOx的主要工况.%The main technologies controlling NOx emission for light diesel vehicle are introduced in this paper.The NOx emission of the typical diesel engines in China is tested.The different technical routes reducing NOx emission in China,EU and USA are comparatively analyzed.A car meeting the US emission standard and employing the SCR technology was tested for cold and hot start conditions.Results show that the NOx emission of the light diesel vehicle decreases in the order of American standard car,the European standard car,and the Middle East standard car.The American car adopting the SCR technology has the best condition coverage.The European car employing the EGR can be optimized to meet the Euro5.It is found that cold start should be responsible for the NOx emission of the American car,and the NOx emission is mainly generated at the low load and accelerating condition for light diesel vehicles.