直喷汽油机颗粒捕集器(GPF)灰分参数试验研究

Experimental Study on Ash Parameters of Gasoline Particulate Filter of Direct Injection Gasoline Engine

为研究汽油机颗粒捕集器(gasoline particulate filter,GPF)中灰分(ash)含量对发动机性能、燃油耗、排气背压、颗粒物排放数量(particle number,PN)的影响,建立灰分累积模型,并以某款发动机作为研究对象,建立了发动机GPF耐久试验台架,验证灰分累积模型的合理性。通过试验,研究了灰分对发动机性能、燃油耗、排气背压、PN排放的影响规律,并分析了灰分随发动机有效运行时间的变化规律及其对GPF碳载量的影响。结果表明,随着灰分的增多,发动机扭矩和功率相比GPF无灰分时都降低,最大降幅达1.2倍,油耗增多,排气背压增大,最大增幅达1.1倍,PN排放先降低后升高;GPF过滤效率直线上升,灰分为30 g时,达到最大,碳载量减少,再生速率加快。为将灰分对发动机的影响降低到最小程度,应限定该发动机的GPF最大灰分量为30g。

In order to study the influence of ash content in GPF on engine performance,fuel consumption,exhaust back pressure,particle number(PN),an ash accumulation model was built and a GPF endurance test bench was set up based on a certain engine to verify the ash accumulation model.The effects of ash on engine performance,fuel consumption,exhaust back pressure,and PN emissions were studied by testing.And the change of ash with the effective running time of the engine and its influence on carbon load were also analyzed.The results showed that,compared with the torque and power of the engine with no ash in the GPF,when ash increased,the maximum torque and power decreased by 1.2 times,the fuel consumption increased,the maximum back pressure increased by 1.1 times,the PN emissions decreased first and then increased,the filtration efficiency of GPF linearly increased and reached the maximum at 30 g of ash,the carbon load decreased,and the GPF regeneration rate accelerated.In order to minimize the impact of ash,the engine should have a maximum ash limit of 30 g.