3D modeling of flow, spray of reductant and surface chemical reaction in diesel urea SCR-NOx catalytic converter

With the aid of CFD (Computational Fluid Dynamic) coupled with chemical reaction dynamics , a three-dimensional modeling was made on a full-sized diesel SCR-NOx catalytic converter system by considering the injection and evaporation of the urea water solution, the subsequent thermal decomposition into ammonia and the surface catalytic reactions in the monolith. The catalyst performances under different loads were also investigated based on the validation of the spray injection model, and the simulated results give a good agreement with the test bench results. The simulated results can be used in optimum design of the diesel SCR catalyst.