驾驶模式对轻型汽油车PN排放影响试验研究

根据GB18352.6-2016中的RDE试验要求,对一轻型汽油车开展车载排放试验,设计了正常运行、急加减速运行两种驾驶模式,分别测取车速、排气温度、PN与CO2排放等数据,并进行数据处理。行程动力学检验分析表明,急加减速驾驶模式的驾驶激烈程度明显高于正常模式,但两种驾驶模式下的行程动力学特性均在有效范围内,CO2窗口的正常性与完整性均符合要求。研究发现,PN排放浓度与排放因子均与车速有较强的正相关性,急加减速驾驶行为下PN排放浓度和排放因子均明显高于正常驾驶模式。统计得出测试车辆的PN排放因子在正常驾驶模式时为3.16×10^10个/km,急加减速驾驶模式为9.05×10^10个/km。相比WLTC工况下国Ⅵ排放限值,正常驾驶、急加减速驾驶模式下RDE试验的PN符合性因子分别为0.05和0.15,低于国ⅥRDE符合性因子标准限值2.1。

Influences of Driving Mode on PN Emission of Light Duty Gasoline Vehicle

According to the requirements of GB18352.6-2016,the RDE tests of normal operation and rapid acceleration and deceleration operation modes were designed and conducted on a light duty gasoline vehicle.The parameters such as vehicle velocity,exhaust temperature,PN and CO2 emissions were measured and processed.The analysis of travel dynamics showed that the driving intensity of rapid acceleration and deceleration operation mode was significantly higher than that of normal operation mode,but the characteristics of travel dynamics in both driving modes were within the effective range,and the normality and integrity of CO2 window met the requirements.The study also indicated that both the PN emission concentration and emission factor had a strong positive correlation with vehicle velocity and they were larger under the rapid acceleration and deceleration operation driving mode.It was statistically concluded that the PN emission factors of testing vehicle were 3.16×10^10 #/km and 9.05×10^10 #/km respectively for the normal and rapid acceleration and deceleration operation driving modes.Compared with the China Ⅵ emission limits under WLTC conditions,the PN conformity factor for RDE test in normal and rapid acceleration and deceleration operation driving modes was 0.05 and 0.15 respectively,which was lower than the RDE conformity factor limit of 2.1.