3D simulation research on urea-SCR DeNO_x catalyst for diesel engine

In order to reduce oxides of nitrogen (NO_x) emanated from a diesel engine, a comprehensive urea selective catalyst reduction (SCR) DeNO_x catalyst was modeled in which numerical simulations were used as a complementary tool for the experimental investigations to make the design decisions, and hence shorten the development process. In this approach, relevant conversion reactions were studied in 1D model, and the parameters obtained in this way were transferred to 3D simulations. According to the results of the study, the conversion of NO and NO₂ increased with the increase in monolith solid temperature. With the increase in the ratio of NO₂/NO, the conversion of NO, NO₂ and NO_x increased resulting in maximum reduction of NO_x at the ratio of 1; beyond this ratio, the conversion of NO₂ and NO_x decreased; however, NO continued to be converted till the ratio was 1.8. The conversion of NO_x decreased with the increase in space velocity.