A Modeling and Experimental Investigation on an Innovative Substrate for DPF Applications 2010-01-0891
XP-SiC is an innovative type of a porous substrate material on the basis of a reaction formed SiC for DPF applications. The high porosity, large pore size inside the cell wall and low specific weight are the special characteristics of this substrate. The aim of the current paper is to present an investigation based on the experimental and modeling approaches to evaluate the back pressure, filtration efficiency and the thermal durability. The latter one was assessed by measuring and predicting the temperature field, as well as calculating the thermal stresses. For this purpose the filter was modeled in the commercial computational code axitrap as a stand-alone tool, in which the conservation equations of mass continuity, momentum, energy and species were solved. The soot filtrations, loading as well as the regeneration by fuel-borne catalyst were modeled. The microstructure properties of the filter and the chemistry parameters for the fuel-borne catalyst were calibrated against engine test bench data. On the engine test bench, the regeneration behavior was determined by loading the filter to different amount of initial soot levels before regeneration. Then the regeneration was tested by running the engine to drop-to-idle (DTI) in order to simulate the worst case scenario. The predicted temperature field and the temperature gradient by axitrap, was the input for the finite element simulation for prediction of thermal stresses in the filter. In addition a benchmark between the catalyzed XP (cXP) and a Cordierite 200/12 was performed regarding the back pressure and filtration efficiency.