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In the present work we apply a computational simulation framework developed for square-cell shaped honeycomb Diesel Particulate Filters to study the filtration, pressure drop and soot oxidation characteristics of recently developed triangular-cell-shaped, high porosity wall-flow filters. Emphasis is placed on the evaluation of the applicability and adaptation of the previously developed models to the case of triangular channels. To this end Computational Fluid Dynamics, asymptotic analysis, multichannel and “unit-cell” calculations are employed to analyze filter behavior and the results are shown to compare very well to experiments available in the literature.

In recent years advanced computational tools of Diesel Particulate Filter (DPF) regeneration have been developed to assist in the systematic and cost-effective optimization of next generation particulate trap systems. In the present study we employ an experimentally validated, state-of-the-art multichannel DPF simulator to study the regeneration process over the entire spatial domain of the filter. Particular attention is placed on identifying the effect of inlet cones and boundary conditions, filter can insulation and the dynamics of “hot spots” induced by localized external energy deposition. Comparison of the simulator output to experiment establishes its utility for describing the thermal history of the entire filter during regeneration. For effective regeneration it is recommended to maintain the filter can Nusselt number at less than 5.

In the present work a practice for conducting experiments and analyzing the fundamental descriptors of Diesel Particulate Filter (DPF) flow resistance behavior is described. The recommended practice addresses each of the following areas: definition of flow resistance descriptors, filter geometrical characteristics, experimental setup and data analysis methods. The sources of errors in each area are identified and a sensitivity analysis is performed. Finally, the recommended practice is applied to several filter materials and configurations tested in the laboratory to determine objectively a set of flow resistance descriptors (namely the filter wall permeability, inlet/outlet loss coefficient) and their error bars. It is expected that application of the recommended practice for the determination of the flow resistance descriptors of DPFs will lead to better quality control procedures and meaningful comparisons of experimental data collected at different laboratories.

A computational lumped parameter model (MTU-Filter-Lumped) was developed to describe the performance of diesel particulate filters (DPFs) during loading and regeneration processes. The model was formulated combining three major sub-models: a filtration model, a pressure drop model, and a mass and an energy balance equation for the total filter volume. The first two sub-models have been widely validated in the literature, while the third sub-model is introduced and combined with the first two sub-models in the present study. The three sub-models combined can give a full description of diesel particulate filter behavior during loading and regeneration processes, which was the objective of the present work. The total combined lumped parameter model was calibrated using experimental data from the literature covering a range of experimental conditions, including different catalytic regeneration means and engine operating conditions.