【摘要】 以一台满足国六排放标准的车用柴油机为试验对象,通过对国六标准试验循环WHSC和WHTC中N₂O的排放特性进行分析和研究。结果表明:后处理的使用会增加柴油机N₂O排放,其中尿素的喷射与否更会显著地影响N₂O的排放;在WHSC和非再生模式WHTC循环中,N₂O在后处理中的产生主要发生在SCR中,循环浓度峰值的产生主要是由于泄露的NH3在ASC中的氧化。再生模式WHTC循环中,N₂O来自SCR及ASC,由于再生排气温度高且THC排放浓度高,DOC中的催化反应也是N₂O的重要来源。更多还原

【Abstract】 Taking a China VI Vehicle Diesel Engine as the test object, the emission characteristics of N₂O are analyzed and studied in the standard test-cycle, WHSC and WHTC. The results show that the use of after-treatment will increase the N₂O emission of diesel engine, and the injection of urea will significantly affect the N₂O emission. In the standard test-cycle, WHSC and non-regeneration WHTC, the generation of N₂O in after-treatment mainly occurs in SCR, and the peak concentration is mainly due to the oxidation reaction of leaked NH₃ in ASC. In WHTC of regeneration mode, N₂O partly comes from SCR and ASC. Because of the high temperature of exhaust and the high concentration of THC emission, catalytic reaction in DOC is also an important source of N₂O emission.更多还原