非均匀壁结构颗粒捕集器深床过滤的模拟研究  

Simulation of Deep-bed Filtration of Gasoline Particulate Filter With Inhomogeneous Wall Structure

作　　者：张彦科[1] 李志军[1] 帅石金[2] 刘世宇 李世龙 刘浩 ZHANG Yan-Ke;LI Zhi-Jun;SHUAI Shi-Jin;LIU Shi-Yu;LI Shi-Long;LIU Hao(State Key Laboratory of Engines,Tianjin University,Tianjin 300072,China;State Key Laboratory of Automotive Safety and Energy,Tsinghua University,Beijing 100084,China)

机构地区：[1]天津大学内燃机燃烧学国家重点实验室,天津300072 [2]清华大学汽车安全与节能国家重点实验室,北京100084

出　　处：《工程热物理学报》2020年第7期1828-1836,共9页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.51976136,No.51576140);清华大学汽车安全与节能国家重点实验室开放基金资助项目(No.KF1818);移动源污染排放控制技术国家工程实验室开放基金资助项目(No.NELMS2019B01,No.NELMS2017A02)。

摘　　要：为描述汽油机颗粒捕集器多孔介质壁的微观结构,本文引入基于概率密度函数的孔径分布和非均匀孔隙率分布。考虑多粒径的入射颗粒,针对汽油机非均匀壁结构颗粒捕集器的深床过滤进行模拟研究。结果表明,颗粒大部分被多孔介质的顶部1/3区域捕集,该区域的孔隙率和渗透率在捕集过程中下降趋势更明显,多孔介质的底部1/3区域对整体过滤贡献很小。随着时间增加,多孔介质壁对各粒径颗粒的捕集效率升高,最具穿透性的粒径变小。在捕集过程中,孔径分布对多孔介质壁的局部微观结构及整体捕集效率和压降的改变有重要影响。A pore size distribution based on its probability density function and a non-uniform porosity distribution are introduced to describe the microstructure of the porous wall of a gasoline particulate filter(GPF)more accurately.The evolution of deep-bed filtration in a GPF with inhomogeneous wall is studied,considering different inlet particle sizes.The results show that most of the particles are captured in the top 1/3 region of the porous wall,in which the porosity and permeability reduce more obviously,and the bottom 1/3 region of the porous wall contributes little to the overall filtration.The filtration efficiency for each particle size increases while the most penetrating particle’s diameter becomes smaller gradually.During the filtration process,the pore size distribution has important Influence on the dynamic changes of local microstructure in the porous wall,the overall filtration efficiency and pressure drop.

关 键 词：汽油机颗粒捕集器 非均匀壁 孔径分布 粒径分布 

分 类 号：TK411.5[动力工程及工程热物理—动力机械及工程]