In this study, with a rectifier grid upstream of ammonia injection grid (AIG), a three-dimensional CFD model was established to optimize the flow field. The effect of the installation height, rectifier grid spacing and plate height on the flow field were investigated. The results show that the uniformity of flow field is improved as the distance between rectifier grid and AIG upstream section decreases. Reducing the grid spacing at high-velocity region is also a valid way to improve the flow field. In addition, the plate height of 200 mm is selected for better performance in optimizing the flow field. Besides adding curved plates at the corner, a suitable rectifier grid arranged upstream of AIG can effectively improve the flow field as well.
Keywords rectifier grid, flow field optimization, CFD, SCR