3D reconstruction and pore-scale modeling of coated catalytic filters for automotive exhaust gas aftertreatment

0497313 - ÚT 2020 RIV NL eng J - Journal Article
Kočí, P. - Isoz, Martin - Plachá, M. - Arvajová, A. - Václavík, M. - Svoboda, M. - Price, E. - Novák, V. - Thompsett, D.
3D reconstruction and pore-scale modeling of coated catalytic filters for automotive exhaust gas aftertreatment.
Catalysis Today. Roč. 320, January (2019), s. 165-174. ISSN 0920-5861. E-ISSN 1873-4308
Institutional support: RVO:61388998
Keywords : catalyst * filter * x-ray tomography * mathematical modeling * CFD * reaction
OECD category: Chemical process engineering
Impact factor: 5.825, year: 2019
Method of publishing: Limited access
https://www.sciencedirect.com/science/article/pii/S0920586117308416

This paper introduces a newly developed methodology for the pore-scale simulation of flow, diffusion and reaction in the coated catalytic filter. 3D morphology of the porous filter wall including the actual distribution of catalytic material is reconstructed from X-ray tomography (XRT) images and further validated with the mercury intrusion porosimetry (MIP). The reconstructed medium is then transformed into simulation mesh for OpenFOAM. Flow through free pores in the substrate as well as through the coated zones is simulated by porousSimpleFoam solver, while an in-house developed solver is used for component diffusion and reactions.
Three cordierite filter samples with different distribution of alumina-based coating ranging from in-wall to onwall are examined. Velocity, pressure and component concentration profiles are calculated enabling the prediction of permeability and component conversion depending on the actual microstructure of the wall. The
simulation results suggest that the gas predominantly flows through remaining free pores in the filter wall and cracks in the coated layer. The mass transport into the coated domains inside the filter wall is enabled mainly by diffusion. Large domains of compact catalytic coating covering complete channel wall result in a significant increase of pressure drop as the local permeability of the coating is two orders of magnitude smaller than that of bare filter wall.
Permanent Link: http://hdl.handle.net/11104/0298211