不同涂覆配方对缸内直喷发动机颗粒物捕集器性能的影响

The influence of different coating formulations on the performance of GPF in direct injection engines

为探讨不同涂覆配方对缸内直喷(GDI)发动机在颗粒物捕集器试验中的性能影响,采用台架标定系统PUMA软件对某GDI发动机不同涂覆颗粒物捕集器样件(GPF-A、GPF-B)进行台架试验,试验中未对发动机进行任何改动。试验结果表明:GPF-A、GPF-B的压差基本一致;在颗粒物捕集器温度为650℃下,随着氧流量的增加,GPF-A、GPF-B的燃烧速率均明显升高,且在相同氧流量下,GPF-A的燃烧速率较高;在氧质量流量为500 mg/s下,随着颗粒物捕集器温度的增加,GPF-A、GPF-B的燃烧速率均明显升高,且GPF-A的燃烧速率较高;GPF-A、GPF-B在700℃断油后的内部温度场变化较为一致,GPF-A在断油18 s后从初始温度710℃上升到最高温度960℃,而GPF-B在断油24 s后从初始温度705℃上升到最高温度942℃;发动机在台架中等负荷(70%额定负荷)、中等转速(3 000 r/min)的工况下运行相同时间,GPF-A捕集的载碳量较小,说明在此工况下,GPF-B的捕集效率优于GPF-A。

In order to investigate the effects of different coating formulations on the performance of gasoline direct injection(GDI) engines in gasoline particulate filter(GPF) tests,the platform calibration system PUMA software was used to carry out bench tests on different coated particulate matter trap samples(GPF-A,GPF-B) of a GDI engine.No changes were made to the engine in the test.The test results show that the pressure difference of GPF-A and GPF-B is basically the same.At a gasoline particulate filter temperature of 650 ℃,with the increase of oxygen flow rate,the combustion rates of GPF-A and GPF-B both significantly increase,and at the same oxygen flow rate,the combustion rate of GPF-A is higher.At an oxygen mass flow rate of 500 mg/s,as the gasoline particulate filter temperature increases,the combustion rates of GPF-A and GPF-B both significantly increase,with GPF-A having a higher combustion rate.The internal temperature fields of GPF-A and GPF-B are consistent after oil cutoff at 700 ℃.GPF-A rises from the initial temperature of 710 ℃ to the highest temperature of 960 ℃ after oil cut-off for 18 s,while GPF-B rises from the initial temperature of 705 ℃ to the highest temperature of 942 ℃ after oil cut-off for 24 s.When the engine runs for the same time at medium load(70%rated load) and medium speed(3 000 r/min) on the test bench,the amount of carbon captured by GPFA is small,indicating that the capture efficiency of GPF-B is better than that of GPF-A under this working condition.