摘要：为了探究柴油机排放颗粒的特性,采用高倍透射电镜、原子力显微镜和小角度X射线散射分析柴油机排放颗粒的粒径分布、微观形貌、孔隙结构和力学特性等物性参数。结果表明:柴油机排气阶段,沿着排气气流方向,颗粒的平均粒径呈增大趋势,聚集态颗粒所占比例逐渐上升;柴油机排气颗粒的二维小角度散射图像具有相似性,基本呈现同心圆分布;随着排气过程的进行,颗粒的散射强度减弱,散射曲线中散射矢量特征值q_min减小,颗粒的吸附力F_at和黏附力F_ad逐渐增大。

关键词：柴油机；排气颗粒；粒径分布；孔隙结构；团聚力

Abstract: In order to investigate the characteristics of diesel exhaust particles，the particle size distribution，micromorphology，pore structure and mechanical properties of diesel exhaust particles were analyzed by high power transmission electron microscopy，atomic force microscopy and small angle X-ray scattering．The results show that during the exhaust phase，along the direction of exhaust gas flow，the average particle size increases，and the proportion of aggregated particles increases gradually．In the exhaust process，the two-dimensional small-angle scattering images of diesel particles are similar，showing concentric circle distribution．As the exhaust process proceeds，the scattering intensity of particles decreases，the scattering vector eigenvalue qmin decreases，and the attractive force F_at and adhesion force F_ad of particles gradually increase．

Keywords: diesel engine; exhaust particles; particle size distribution; pore structure; agglomeration