Based on experimental data from engine after-treatment tests, the diesel particulate filter (DPF) microscopic channel model was constructed using UG, and the accumulation of particulate matter (PM) in the deep bed filter layer and carbon deposit layer was analyzed through computational fluid dynamics (CFD). A comprehensive study was conducted on the exhaust gas flow characteristics and PM movement within the DPF channel, and focus on the effects of PM distribution type on capture and regeneration characteristics. The results show that with the increase in particle size in the exhaust, the distribution of PM concentration along the axial position of the channel shows a trend of gradually shifting from 0.2 to 0.25 m (rear section) to 0.125–0.2 m (front section). In particular, PM with 1 μm particle size has a large motion inertia, which is easy to move out of the airflow and deposit in the middle part of the channel. For PM in the front and middle sections of the channel, the airflow obstruction is relatively small, but the heat transfer loss is large, which is not beneficial for PM regeneration in the rear section. Therefore, with the distribution of LID, PD-1, and PD-2, the regeneration efficiency is relatively low, at 50.84%, 55.01%, and 54.59%, respectively.

中文翻译：

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柴油机颗粒过滤器通道内气体流动及PM运动特性分析

基于发动机后处理试验数据，利用UG构建柴油机颗粒过滤器（DPF）微通道模型，并通过计算流体分析颗粒物（PM）在深层过滤层和积炭层的积累情况动力学（CFD）。对DPF通道内的废气流动特性和PM运动进行了综合研究，重点研究了PM分布类型对捕集和再生特性的影响。结果表明，随着排气中颗粒尺寸的增加，PM浓度沿通道轴向位置的分布呈现出从0.2~0.25 m（后段）逐渐向0.125~0.2 m（前段）移动的趋势。 。特别是1μm粒径的PM，运动惯性较大，很容易移出气流并沉积在通道中部。对于通道前段和中段的PM，气流阻碍相对较小，但传热损失较大，不利于后段的PM再生。因此，随着LID、PD-1和PD-2的分布，再生效率相对较低，分别为50.84%、55.01%和54.59%。