Influence and strategy optimization of fuel injection timing on PN and fuel consumption

During the development of a CN Ⅵ light vehicle equipped with GDI gasoline engine, phenomenon high PN appeared. In response to operating conditions engine running in WLTC cycle, corresponding SOI sweep was performed on dyno bench. The emissions has reduced by optimizing SOI. results show that when is sufficiently advanced, oil film formed collision spray and piston causes increase significantly. order avoid deterioration emissions, should be appropriately postponed. low load conditions, it more appropriate calibrate at 295°CA 290°CA. medium speed area, suitable set 300°CA or later. higher area can slightly advanced if necessary. And impact fuel consumption obvious speeds, but not loads speeds.