对同一台轻型两用燃料（C N G和汽油）车使用同一批次基准天然气和基准汽油，在底盘测功机上进行NEDC ，FTP75和WLTC循环对比试验，使用CVS定容取样系统和ELPI设备分析颗粒物等排放。研究发现：3种循环中，试验车辆燃用CNG和汽油，排放颗粒物在 Dp ＝40 nm和 Dp ＝330 nm附近均出现峰值，Dp ＝40 nm处汽油峰值远高于CNG ，Dp ＝330 nm处CNG峰值略高于汽油；CNG的PN和PM的排放率随车速的升高而增大，在较低的匀速工况下增长幅度较小，高速工况下增长幅度较大；CNG在NEDC循环中排放的核态和聚集态颗粒物各占50％左右，FTP75和WLTC循环中排放的聚集态颗粒物占比高于NEDC ；CNG在NEDC循环中单位里程颗粒数和颗粒总数最多，FTP75和WLTC循环中单位里程颗粒数基本相同；WLTC循环中排放的颗粒物质量总量最多，FTP75和NEDC循环中排放的颗粒物质量总量基本相同；FTP75和WLTC循环中单位里程排放的颗粒物质量基本相同，约为N EDC循环的2倍。%For a light duty dual fuel vehicle ,the NEDC ,FTP75 and WLTC experiments of standard natural gas and gasoline were conducted on a chassis dynamometer and the analysis of particle emission was completed through the CVS sampling sys‐tem and ELPI equipment .The results show that the particle emissions of vehicle fueled with CNG and gasoline reach the peak at the particle diameter of 40 nm and 330 nm in all three driving cycles .The peak of gasoline is higher than that of CNG at 40 nm and the peak of CNG is higher than that of gasoline at 330 nm .The PN and PM emission rate of CNG increase with the increase of vehicle velocity and the increase is small at low and uniform speed conditions and large at high speed conditions .The nuclear and accumulation mode particles of CNG take up 50% respectively in NEDC cycle and the accumulation mode particle of FTP75 and WLTC is higher than that of NEDC .The total number of particles and particle number per kilometer in NEDC and the total particulate mass in WLTC cycle are the largest .The particle number per kilometer in FTP75 and WLTC cycle are mainly the same ,while the same result for the total particulate mass in FTP75 and NEDC cycle .In addition ,the particulate mass per kilometer in FTP75 and WLTC cycle are mainly the same ,which is twice of that in NEDC cycle .
展开▼
