Use of the MTU 1D 2-layer CPF Model to Understand Filtration and Oxidation Characteristics of a DOC-CPF System
Kiran Premchand, Michigan Tech University
A 1D 2-layer Catalyzed Particulate Filter (CPF) model has been developed at MTU to study the flow, filtration and oxidation characteristics of a DOC-CPF (diesel oxidation catalyst and a catalyzed particulate filter). The filtration process used in the CPF model employs a “two filters in series” approach, modeling sequential filtration by PM cake layer and substrate wall. Regeneration processes considered in the process include PM oxidation by thermal and NO2/temperature means, as well as NO2 production in the CPF (and PM oxidation due to the NO2 produced) as the exhaust mixture passes through the PM cake and catalyst layer in the substrate wall. Emissions data from a John Deere 6.8 liter in-line 6-cylinder engine with a cooled low-pressure EGR loop at various speeds and load conditions were used to calibrate the input parameters needed for the CPF model. A brief overview of the CPF model is discussed. Modeling and experimental results from the 25% and 100% of full load at rated speed data are presented. Conclusions about the filtration and oxidation characteristics of the CPF in a DOC-CPF system reached from the modeling output results are discussed. The modeling data results in a better understanding of the filtration and oxidation characteristics of the CPF.