A mathematical model for the dynamic particulate filtration in diesel foamfilters

Diesel Particulate Filters (DPFs) are probably the most effective means for trapping the exhaust-emitted particulate from diesel engines. Foam type fi lters become a promising alternative to the common wall flow filters, since they are effective in filtering small size particles and provide a larger specific surface area for catalytic coatings. A mathematical model taking i nto account the significant phenomena during the dynamic filtration of foam filters is developed. The model predicts the filtration efficiency and the induced backpressure as function of the geometric filter properties and op erating conditions. Due to the particular structure properties of the foam filters it is necessary to employ a tunable parameter, which accounts for t he influence of non-Stokes flow in foam filters. This parameter is easily d erived by simple measurements. The model is employed to identify and unders tand the critical parameters of the filtration in foam filters. Indicative parametric runs are presented, which illustrate the applicability of the mo del in system optimization procedures.