Filtration and regeneration modeling for particulate filters with inhomogeneous wall structure

A new advanced filtration model for diesel particulate filter (DPF) is presented. The model is able to account for the distribution of soot particle size and different material and filtration properties for non-homogeneous wall structures. The impact of a thin dense layer on top of the inlet channels of a DPF on filtration, pressure drop and passive regeneration is investigated using the model. In agreement with previous literature experimental studies, significant improvement in the filtration efficiency is shown. The increased pressure drop of the empty filter is quickly outbalanced during loading due to less soot accumulation inside the wall. The negative effect of the layer technology on passive regeneration of catalyzed filters is demonstrated by solving the reaction–diffusion equations in the wall.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (290 K)Download as PowerPoint slideHighlights► An advanced DPF filtration model for non-uniform wall structures is presented. ► Depth-filtration efficiency increases with application of a thin layer on top. ► Soot-loaded DPF pressure drop decreases if a thin layer is applied. ► Passive regeneration rates are reduced due to NO2 back-diffusion inhibition.