Porous Medium Model in Computational Fluid Dynamics Simulation of a Honeycombed SCR DeNOx Catalyst

The commercial computational fluid dynamics software FLUENT was used to simulate the flow and chemical reaction process of a honeycombed SCR DeNOx catalyst. In the calculation model, the porous medium model was applied to describe the wall body region of the honeycombed catalyst and the ordinary flow model in order to define the honeycombed channel region. From the comparison between the two gas diffusion rates within catalyst pore structure and gas medium, their effects on the SCR DeNOx reaction rate were analyzed. A correction factor of the chemical reaction rate was created to modify the porous medium model in order to accurately calculate the chemical reaction process of the catalyst model. The study results indicated that the combination between porous medium model and reaction rate correction factor could compensate the deviation of calculated reaction rate and the interfacial diffusion problems.