基于可视化单通道实验系统,采用激光位移测量方法,对柴油机颗粒在陶瓷捕集器内的沉积过程进行了在线测量.研究结果发现,颗粒沉积过程分为4个阶段:深床期、长树期、搭桥期和颗粒层期；颗粒层厚度的增加在长树期迅速增长,而后在颗粒层期呈缓慢增加的趋势.颗粒层过滤期颗粒层的孔隙结构受过滤速度的影响,过滤速度增大,颗粒层的渗透系数和孔隙率减小,形成的颗粒层致密.实验结果证实了当Pe＜l时,渗透系数和孔隙率随Pe的增大而减小,且变化显著；当Pe＞1时,渗透系数和孔隙率随Pe数的变化趋于平坦.%Based on the visualized single channel filtration system, the deposition configuration of soot layer in die-sel particle filter was investigated online by laser displacement measurement. The experimental results show that the filtration process can be divided into four stages: deep bed filtration, particle 'tree' growth, particle 'tree' connection and particle layer filtration. Soot layer thickness increases rapidly at the second stage and then increases slowly at soot layer filtration stage. Filtration velocity has great effect on soot deposition configuration at soot layer filtration stage. With the increase in filtration velocity, permeability coefficient and the porosity of soot layer decrease, and soot layer becomes denser. When Peclet number (Pe) < 1, permeability coefficient and the porosity of soot layer decrease significantly with the increase of Pe, while when Pe>1, permeability coefficient and the porosity of soot layer nearly remain constant.
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