The influence of a 2-component model on the computed regeneration behaviour of an uncoated diesel particulate filter

The present work deals with the modelling of diesel particulate filters. Model extensions as well as further development regarding soot monitoring during regeneration are investigated. A slip flow model, leading to an improvement of computed pressure drop profiles, a shape correction term, considering an increasing perimeter which changes the wall flow through the particle layer, and a 2-component model, which distinguishes between soot as cake upon and soot within the filter wall, have been implemented and the effects on previous results discussed. However, the main focus of the work is laid upon a sensitivity analysis regarding soot combustion within the pore combined with a discussion upon judging the accuracy of computed results. In order to compare experimental and computed results an uncoated SiC filter with 200 CPSI and 15 mil wall thickness was used. All experiments were conducted under real-world conditions on an engine test bench, which includes filter loading and regeneration. It can be shown, that the 2-component model effects positively the simulation of filter loading, as the filtration can be divided into deep bed and cake filtration. Due to the sensitivity analysis on kinetic parameters different effects on pressure drop and soot loading profiles during regeneration have been investigated. A faster soot combustion within the filter wall shows only a slight effect on the total soot loading curve. However, there is a strong influence on the pressure drop profile, which lowers the deviation between experiment and simulation.