| Popis: |
A diesel particulate filter (DPF) is an important technology that can meet emissions regulations of particulate matter (PM). Generally, high filtration efficiency is achieved, after a thin soot layer is formed on the surface of a porous ceramic filter wall, but some PMs may pass through the filter in the early period. Therefore, an investigation of the soot layer formation for the PM filtration mechanism is needed. In this study, the filtration efficiency of SiC-DPF in the early period was measured by a PM counter, together with SEM observation of the soot layer formation. In addition, the quantification of soot layer formation was tested in terms of the surface roughness of the filter wall surface. Results showed that as the soot layer was formed, the value of surface roughness became smaller, with filtration efficiency higher, and there is a correlation between the filtration efficiency and the surface roughness. Thus, the degree of soot layer formation can be evaluated quantitatively by the surface roughness. |
