以一台国六甲醇增程式发动机为研究对象，搭建排放测试系统，进行了重型车国六阶冷热态WHTC循环试验，研究了标准循环工况下N2O和NH3的排放特性。研究表明：甲醇发动机原机排放中N2O和NH3排放极低，但使用三元催化后处理系统后，N2O和NH3的排放量会大幅增加；WHTC循环中，N2O排放较高的区域集中在排气温度为400 ℃左右的低温段，且从高转速变化为低转速时会形成N2O排放值，而在高温阶段几乎没有N2O排放；WHTC循环中，NH3排放主要集中在排温500~550 ℃区间内，在低于500 ℃的低温段和高于550 ℃的高温段排放量极低，且循环平均NH3排放热态明显高于冷态。
For a China Ⅵ methanol extendedrange engine, the emission measurement system was built and the China Ⅵ cold and hot WHTC test for heavyduty vehicle was carried out, and theN2O and NH3 emission characteristics were researched. The results show that the N2O and NH3 emission of original engine is extremely low, but will greatly increase after using the three-way catalytic aftertreatment system. In WHTC cycle, the high N2O emission concentrates in the low temperature stage of about 400 ℃ exhaust temperature and reaches the peak when the speed changes from high to low, while there is little N2O emission in the high temperature stage. NH3 emission mainly concentrates in the temperature range of 500~550 ℃ and becomes rare in the temperature section below 500 ℃ and above 550 ℃.Besides, the cycle average NH3 emission in the hot state is significantly higher than that in the cold state.
