Abstract: Diesel oil is injected into upriver vent-pipe of diesel oxidation catalyst (DOC) and mixed with the engine exhaust. The diesel oil is oxidized through the catalytic converter and gives out heat to improve the engine exhaust temperature, thus realizing the regeneration of diesel particulate filter(DPF). The whole system consists of fuel injector, oxidation catalytic converter and particulate filter. The regeneration characteristics of this system are researched on the engine bench, including the attainable temperature of exhaust after oxidation catalytic converter at different simulation vehicle speeds and different injection quantities; the temperature rise characteristics after catalytic converter during regeneration; the back pressure characteristics of particulate filter in regeneration process; and the analysis on the economy and secondary pollution of the regeneration method. The results show that when simulation speed is greater than 60 km/h, injection and regeneration can be carried out. The whole regeneration time is 330 s, the economy of the regeneration method is good, and the secondary pollutants are mainly HC and CO.

Key words: Diesel engine, Diesel oxidation catalyst, Diesel particulate filter, Regeneration