增压直喷汽油机细小颗粒物排放特性研究  

Emission Characteristics of Sub-23 nm Particles from a Turbocharged Direct-Injection Gasoline Engine

作　　者：侯宇旭 葛蕴珊[1] 王欣[1] 苏盛 谭建伟[1] 郝利君[1] HOU Yuxu;GE Yunshan;WANG Xin;SU Sheng;TAN Jianwei;HAO Lijun(School of Mechanical Engineering,Beijing Institute of Technology,Beijing 100081,China;Xiamen Environment Protection Vehicle Emission Control Technology Center,Xiamen 361021,China)

机构地区：[1]北京理工大学机械与车辆学院,北京100081 [2]厦门环境保护机动车污染控制技术中心,厦门361021

出　　处：《内燃机工程》2021年第4期24-29,37,共7页Chinese Internal Combustion Engine Engineering

基　　金：国家自然科学基金项目(51806015);首都蓝天行动培育项目(Z181100005418012)。

摘　　要：在一辆国六增压直喷、未安装颗粒捕集器的汽油车上分别采用常温(23℃)全球轻型车统一测试循环(worldwide harmonized light vehicles test cycle,WLTC)、常温(23℃)RTS95和低温(0℃)实际道路排放(real drive emission,RDE)测试循环对粒径在23 nm以上和10 nm以上的颗粒物数量排放进行了同步测试研究,以研究增压直喷汽油车的细小颗粒物(粒径10 nm~23 nm)排放特性。结果表明,在常温WLTC、RTS95及低温RDE循环测试中,10 nm以上颗粒物的数量排放比国六标准规定的23 nm以上颗粒物分别高32.4%、30.4%和15.6%。无颗粒捕集器时,急加速、减速和怠速工况细小颗粒在总颗粒物排放中的占比明显增加;冷起动和暖机阶段细小颗粒物的排放占比很低。细小颗粒主要在车辆充分暖机和三元催化器(three-way catalyst,TWC)起燃后产生;较低的环境温度并未引起细小颗粒物的明显增加。A simultaneous test study on the particle number emission of particles whose diameters are greater than 23 nm and 10 nm was conducted on a China-6 certified,turbocharged,direct-injection gasoline engine vehicle without particulate filter using the worldwide harmonized light vehicles test cycle(WLTC)and RTS95 test cycle at ambient temperature(23℃),and real drive emission(RDE)test cycle at low temperature(0℃),to research the emission characteristics of sub-23 nm particles from turbocharged direct-injection gasoline engine vehicles.The results showed that the emissions of numbers of particles whose diameters are above 10 nm were 32.4%,30.4%and 15.6%higher than those of China-6 standard required particles whose diameters are above 23 nm in the ambient-temperature WLTC,ambient-temperature RTS95 test cycle and low-temperature RDE cycle respectively.Without particulate filter,the percentage of sub-23 nm particles in the total particle emissions increased significantly during harsh accelerations,decelerations,and idle conditions,but it was very low in the cold-start and warm-up stages.Sub-23 nm particles mainly formed after the vehicle was fully warmed-up and the three-way catalyst converter was fired.Lower ambient temperature was not beneficial to the formation of sub-23 nm particles.

关 键 词：汽油机 细颗粒物 颗粒物数量 排放 

分 类 号：TK417.126[动力工程及工程热物理—动力机械及工程]