不同气氛下微粒捕集器的离线再生

基于NO2、NO2/O2以及O3与PM的化学反应模型，探究了气氛对微粒捕集器（DPF）离线再生效果的影响。研究结果表明，NO2/N2的气氛下，PM的起燃温度为250℃，而在NO2/O2/N2气氛下，PM的起燃温度降至150℃左右，但在O3/N2气氛下，PM可在低于100℃的再生温度下起燃。在3种气氛下，DPF的再生效率受再生温度的影响均较为明显。当再生温度较低（≤250℃）时，O3/N2气氛下，DPF的再生效果最好，且实现完全再生的时间最短；当再生温度较高（>250℃）时，NO2/O2/N2气氛下，DPF再生效果最好，且温度越高，实现完全再生的时间越短。在所选的再生温度范围内，O3/N2气氛下的壁面最大温度梯度峰值均高于NO2/N2和NO2/O2/N2气氛，但远小于DPF安全的温度梯度极限。

DPF offline regeneration under different atmospheres

Effects of atmosphere on diesel particulate filter(DPF) offline regeneration were studied based on the chemical reaction models of NO2, NO2/O2, O3,and PM. The results show that the light-off temperature of PM under a NO2/N2 atmosphere is about 250℃, and it drops to about 150℃ under a NO2/O2/N2atmosphere. The light-off temperature of PM under an O3/N2 atmosphere is lower than 100℃. The regeneration temperature has a significant impact on the efficiency of DPF regeneration under the three atmospheres. When the regeneration temperature is lower (≤250℃), the effect of DPF regeneration is best under an O3/N2 atmosphere and the time for complete regeneration is the shortest. However, when the regeneration temperature is higher (>250℃), the effect of DPF regeneration is best under a NO2/O2/N2 atmosphere and the time for complete regeneration decreases with the increase in temperature. With the regeneration temperatures selected in this study, the peak of the maximum gradient of the solid temperature under an O3/N2 atmosphere is larger than that under a NO2/N2 or NO2/O2/N2 atmosphere, which is much less than the safe gradient temperature.