PN emission characteristics of light-duty GDI vehicles under real-driving conditions

This study investigates the PN emission characteristics of direct injection petrol vehicles in Real Driving Emission (RDE) tests using a Portable Emission Measurement System (PEMS). The results of the study show that particulate matter emissions are mainly concentrated in suburban and high-speed conditions, and there is a significant positive correlation between PN emission levels and engine in-cylinder temperature. The higher the speed, the higher the emission level, but rapid acceleration will cause a large amount of particulate emissions in a short period of time. When VSP is above 0 kW/t, the higher the VSP, the higher the PN emission.