Abstract:Abstract: Diesel Particulate Filter (DPF) has been widely used in diesel emission control. The accumulation of particulate matter(PM) results in higher engine back pressure and lower engine fuel economy. Therefore, DPF regeneration must be carried out to reduce PM and ensure effective operation of the engine. In order to compare the difference of characteristics of DPF regeneration temperature between plateau and plain environment, and provides a reference for the safe and reliable regeneration of DPF in plateau environment, the changes of the temperature characteristics and temperature gradients of DPF at 550, 575 and 600 ℃ for 0, 1 000 and 1 960 m elevations were compared and analyzed by bench test in this paper. The results showed that the temperature change of DPF substrate was consistent under both sea level and high altitudes environment. The temperature decreased from DPF center to edge in the radial direction, and increased from DPF inlet to outlet in the axial direction. The temperature at the center of DPF outlet was the highest. The temperature of DPF substrate increased with the increase of regeneration temperature and altitude. the maximum peak temperature for regeneration temperature of 575 ℃ at 0, 1 000 and 1 960 m altitudes were 3.8%, 9.5% and 17.8% higher than that of 550 ℃ respectively, and the maximum peak temperature for regeneration temperature of 600 ℃ were 10.1%, 16.4% and 19.4% higher than that of 575 ℃ respectively. Compared with that at 0 m altitude, the maximum peak temperature for regeneration temperature of 550, 575 and 600 ℃ at 1 000 m altitude increased by 4.6%, 10.3% and 16.6% respectively. The maximum peak temperature at 1 960 m altitude were 6.3%, 14.3% and 17.2% higher than that at 1 000 m. With the increases of altitude, the radial and axial temperature gradients of DPF carrier increased. Compared with that at 0 m altitude, the maximum radial temperature gradients for regeneration temperature of 550, 575 and 600 ℃ at 1 000 m altitude increased by 48.7%, 118.9% and 145.5% respectively, the maximum axial temperature gradients increased by 84.3%, 81.6% and 198.2% respectively, the maximum radial temperature gradient at 1 960 m altitude were 65.5%, 91.1% and 166.9% hgher than that at 1 000 m altitude respectively, and the maximum axial temperature gradients were 20.2%, 83.2% and 43.2% higher than that at 1 000 m. It was found that the temperature of diesel oxidation catalyst (DOC) inlet in plateau environment was higher than that of plain, resulting in higher inlet temperature rising rate, peak temperature of carrier and temperature gradient of DPF in plateau environment. Therefore, the risk of DPF damage was more likely to occur at high altitude environments. In order to ensure the safe and reliable regeneration of DPF in plateau environment, the regeneration temperature at 1 000 m altitude should be below 600 ℃, and that at 1 960 m altitude should be below 575 ℃ to reduce the temperature gradient and prevent excessive local thermal stress.