Open AccessNumerical Simulation of NOx Reduction in a SCR System
Author(s) -
Artem Blinov,
N. A. Kiselev,
Leonid Myagkov
Publication year - 2021
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/1111/1/012009
Subject(s) - nox , selective catalytic reduction , computational fluid dynamics , reduction (mathematics) , catalysis , environmental science , process engineering , nitrogen oxide , mixing (physics) , diesel engine , diesel fuel , flow (mathematics) , work (physics) , inlet , mechanics , automotive engineering , chemistry , engineering , mechanical engineering , physics , mathematics , combustion , biochemistry , geometry , organic chemistry , quantum mechanics
The stringent limits of emission standards require advanced emission control technologies to be used in modern on and off highway diesel engines. They include both in-cylinder and aftertreatment measures where the latter now have become almost mandatory. Selective catalytic reduction aftertreatment systems are widely used for nitrogen oxide (NO X ) conversion in exhaust gases into harmless N 2 . To reduce time and costs, at the design stage of SCR systems numerical modelling is applied. Mathematical models and methods providing high prediction accuracy with and acceptable level of computational efforts are required. In this work an approach for complete simulation of SCR systems based on the coupling of commercial CFD software with developed multichannel 1D catalyst model is presented. The first one is used to carefully describe processes occurring upstream in the catalytic converter, particularly, during urea water solution injection and flow mixing. As a result, the distributions of flow parameters at catalyst inlet are derived. They are subsequently imported as boundary conditions into a developed multichannel catalyst model that allows one to take them into account when calculating NOx conversion efficiency. Based on the proposed approach a SCR system was simulated. The effect of non-uniform distributions of NH 3 concentration and the gas flow velocity at the catalyst inlet on its performance was investigated. It has been shown that they have a great impact on NO X conversion and should be taken into account during the catalyst modelling.