柴油机不同负荷下排气颗粒作用力与形态分析  

Analysis on interaction force and morphological characteristics for particles under different loads

作　　者：孙旭[1,2] 何仁[1] SUN Xu;HE Ren(Jiangsu Province Key Laboratory of Automotive Engineering,Jiangsu University,Zhenjiang,Jiangsu 212013,China;Nantong Shipping College,Nantong,Jiangsu 226010,China)

机构地区：[1]江苏大学江苏省汽车工程重点实验室,江苏镇江212013 [2]南通航运职业技术学院,江苏南通226010

出　　处：《江苏大学学报（自然科学版）》2019年第1期51-55,共5页Journal of Jiangsu University：Natural Science Edition

基　　金：南通航运职业技术学院重点科技项目(HYKJ2014A01);江苏省汽车工程重点实验室开放基金资助项目(QC201106)

摘　　要：采用原子力显微镜与高分辨透射电镜,分析了单缸柴油机3 600 r·min-1不同负荷(50%,75%和100%)下排气颗粒的力学参数和形态特征.测量结果表明:在相同转速下,随着负荷的增大,颗粒物的吸引力Fat增大,分别为1. 31,1. 64和2. 28 nN;颗粒的黏附力Fad和黏附能垒Wad升高,Fad分别为3. 46,4. 15和4. 71 nN,Wad为1. 45×10^(-16),1. 81×10^(-16)和2. 11×10^(-16)J,这表明,颗粒间的黏附性增强,颗粒间能量势垒增大,颗粒团聚更为稳定,同时,随着负荷的增大,颗粒逐渐由枝状演变为聚集状,团聚程度增强,颗粒呈山峰状堆积,颗粒致密度、团簇大小均增大;颗粒间作用力的变化与颗粒形态的影响关系较为明显,主要表现为吸引力、黏附力、黏附能垒的增大,将促进颗粒的团聚,增强团聚颗粒的致密程度.Atomic force microscopy and high power transmission electron microscope were used to study the interaction force and morphological characteristics of exhaust particles,which were collected at 3 600 r·min^-1 and under different loads of 50%,75%and 100%.The results show that at the same speed,with the increasing of load,the attraction force Fat of particles is increased with 1.31,1.64 and 2.28 nN,respectively.The force of adhesion F ad and the adhesion energy Wad are increased,and Fad values are 3.46,4.15 and 4.71 nN with W ad values of 1.45×10^-16,1.81×10^-16 and 2.11×10^-16 J,respectively.The adhesion and the energy barrier among particles are increased,and the agglomeration of particles becomes more stable.With the increasing of load,the particles are gradually evolved into agglomeration from branch,and the agglomeration degree is increased with mountainous accumulation of particles,increased grain density and cluster size.The relationship between the interaction of particles and the effect of particle morphology is obviously due to the increasing of attraction force,adhesion force and adhesion energy barrier,which can promote the agglomeration of particles and enhance the compactness of agglomerated particles.

关 键 词：柴油机 负荷 作用力 形态特征 颗粒 

分 类 号：TK421.2[动力工程及工程热物理—动力机械及工程]