Visualization of the PM Deposition and Oxidation Behavior Inside the DPF Wall

We investigated filtration and oxidation behavior of secondary particle of particulate matter (PM) in the diesel particulate filter (DPF) wall using a newly developed visualization technique. The observations from magnified cross section view of the test piece cut out from full sized DPF made of Cordierite DPF and SiC. DPF. Only in the beginning of the filtration process, the PM penetrates into deep inside of the DPF wall. And in the PM forced oxidation process, the PM in the wall was oxidized first, then the PM cake layer on the DPF wall thinner by oxidized from contact part with the DPF wall. We carried out these observations with the SiC DPF. Further, we have tried to estimate the activation energy of the PM oxidation from the shrinking form of accumulated secondary particles of PM inside of the cordierite DPF loaded by platinum (Pt). We confirmed that the experimented value of the activation energy is close to that of former researchers.