Experimental Investigation for NH₃ Emission Characteristics of Light-Duty Vehicle

Ammonia (NH₃), as one of the main components of light-duty vehicle emissions, its emission requirements are most likely to be considered in the next stage of emission regulations, with the increase in vehicle ownership and the tightening of emissions regulations worldwide. Therefore, it is necessary to investigate the characteristics of NH₃ emission in automobile exhaust in advance, which is also beneficial to reducing the secondary particulate matter in the atmosphere. In this paper, the emission experiment of a light-duty gasoline vehicle was carried out under different test cycles and ambient temperatures. The emission characteristics of NH₃ were analyzed. The representative conditions of NH₃ formation and its associated relationship with other emission components are emphasized. The data indicated that the cold starting phase and long-term continuous acceleration are the key representative conditions. The significantly positive correlation between the emissions of NH₃ and CO is shown. Here, the emergence of NH₃ is accompanied by the large production of CO. But the correlation of NH₃ with NO_x or THC emissions is not obvious.