利用外加热源再生台架,测试了受来流热冲击时柴油机颗粒捕集器(DPF)白载体的内部温度场分布,分析各种因素对载体最高温度Tmax、最大升温速率Kmax、末端温度梯度极值(dT/dy)max的影响规律。研究结果表明:提高来流温度,Tmax呈线性增大,Kmax增加不明显,(dT/dy)max也增大,有助于增强载体的传热性能;提高来流流量,Tmax增加不明显,Kmax则线性增大,(dT/dy)max略有降低,也有助于增强载体的传热性能;增加载体长度,Tmax、Kmax、(dT/dy)max均降低,载体传热性能降低。增加载体孔目数(CPSI),Tmax和Kmax增大,(dT/dy)max减小,载体传热性能增强;在载体末端添加热惯性体后,Tmax和Kmax基本不变,(dT/dy)max明显减小,对载体的内部温度分布影响不大,但可大幅度降低载体末端内部热应力。
On the diesel particulate filter(DPF) regeneration bench with additional heating sources, temperature distribution inside the filter was measured under high temperature gas flow shock condition, effects on maximum temperature Tmax, maximum heated rate K and maximum end radial temperature gradient of the DPF (dT/dy)max were analyzed. Experimental results show that with gas flow temperature increasing, Tmax increases linearly and Kmax nearly keeps constant, while the (dT/dy) increases also. With increase of gas flow , Tmax rises slightly, Kmax increases linearly, while the (dT/dy)max decreases slightly. Both gas flow temperature and rate increase can enhance the filter heat transfer performance. With increase of the filter length, all of Tmax, Kmax and (dT/dy)max decrease, and the filter heat transfer performance is weakened. With increase of CPSI, Tmax and Kmax increase, while (dT/dy)max decreases, and the filter heat transfer performance is enhanced. Added a thermal inertia substance after filter end, the Tmax and K nearly keep constant, while the (dT/dy)max decreases significantly. Though the influence on temperature distribution inside the DPF substrate is little, while it can greatly reduce the thermal stress appeared in DPF outlet.