Abstract: This paper studies the surrounding thermal field of a China VI heavy diesel commercial vehicle under diesel particulate filter (DPF) regeneration conditions, and proposes reasonable arrangement principles and methods of the heat source surrounding system to further improve the safety and reliability of vehicle operation. Firstly, the whole process of DPF regeneration and the temperature field at different distances are simulated by computational fluid dynamics (CFD). Secondly, the experiment verifies the four stages of DPF active regeneration, the temperature field at different distances and the surface temperature of the peripheral parts under the steady regeneration condition. Finally, the data under different working conditions are compared and analyzed. The results show that during the steady parking regeneration period of DPF, the internal air flow temperature can reach more than 600 ℃, and the highest temperature at the exhaust pipe joint is 235℃. The temperature field presents a nonlinear downward trend with the increase of distance, showing the thermal decay law of the closer to the heat source, the faster the temperature drop, the farther the distance from the heat source, the slower the temperature drop. The distance between the peripheral parts and the heat source is greater than 200 mm and can be reduced to below 80 ℃, which can effectively prevent the heat damage caused by the after-treatment system.

Key words: DPF regenerative conditions; heavy commercial vehicle; after-treatment system; exhaust system; temperature field; heat source; thermal radiation

摘要： 文章针对某国六重型柴油商用车在柴油颗粒过滤器（DPF）再生工况下的周边热场进 行研究，提出热源周边系统合理的布置原则和方法，进一步提升整车运营的安全性和可靠性。 首先，对 DPF 再生全过程和不同距离下的温度场进行计算流体动力学（CFD）仿真分析；其 次，试验验证了 DPF 主动再生四个阶段、稳态再生工况下不同距离温度场及周边件的表面温 度；最后，进行了不同工况下的数据对比分析。结果表明，在 DPF 稳态驻车再生期间，内部 气流温度可达到 600 ℃以上，排气接管处最高温度为 235 ℃，温度场随着距离的增大呈非线 性下降趋势，表现出距离热源越近、温度下降越快，距离热源越远、温度下降减缓的热衰减 规律，周边零部件与热源距离大于 200 mm 以上可降低至 80 ℃以下，能够有效防止后处理系 统产生的热害影响。

关键词: DPF 再生工况；重型商用车；后处理系统；排气系统；温度场；热源；热辐射