UREA-SCR-technology - Performance of structured metallic substrates

SCR technology has proven its ability to significantly reduce NO _X emissions to fulfill future emission legislations. The key to this technology is the generation of ammonia on-board to reduce the NO_X. Ammonia generation catalyst systems need to be highly efficient in a limited packaging space. The influence of physical parameters of the catalyst's substrate such as thermal mass, hydraulic diameter and geometric surface area on catalyst's efficiency is well known, but the transport processes in structured metallic substrates are still an object of investigation. A numerical study for 3 structured substrates was carried out, and the results were compared with experimental data. An increase of the volumetric efficiency was found when structured substrates were applied. The numerical results are in good accordance with the experimental data and therefore proven to be an excellent tool for channel design optimization.