Measurement of Multi-Dimension Soot Distribution in Diesel Particulate Filters by a Dynamic Neutron Radiography

A key component in pollution control for a diesel engine is a diesel particulate filter (DPF). However, the performance of a diesel particulate filter will change with increasing soot loadings and thus may require regeneration. Improved understanding of diesel particulate filters is dependent upon knowledge of the local soot deposition distribution within the DPF. Neutron radiography (NR) has been identified as an effective means of non-destructively identifying hydrogen or carbon based components of particulate matter (PM). In this work, neutron radiography is used to measure multi-dimension soot deposition profiles of DPFs containing diesel soot loadings of 1g to 5g. The results show non-uniform axial, radial, and azimuthal soot distributions. The non-uniformity also increases with soot loading. The capability of neutron radiography to visualize soot multi-dimension distribution measurements has been demonstrated.