SCR Modeling and Simulation
Daniel Chatterjee, DaimlerChrysler AG
Design, application and optimization of the SCR system is a complex process involving the optimization of different parameters like the urea dosing strategy, SCR catalyst position, size and cell density. More complexity is added if combined systems like DOC+SCR or CDPF+SCR are used. Development only by experiments is very time consuming and costly. Therefore, the application of numerical simulations during the development process is a key factor. A predictive simulation model is required for this task. Hence, the model has to be based on chemical and physical fundamentals.
The talk will give an overview at the exhaust gas aftertreatment modeling approach for combined systems at DaimlerChrysler. The focus will be SCR catalyst modeling. The fundamentals of the modeling approach along with the modelling of the reaction kinetics and strategies for finding kinetic parameters will be discussed. The prediction quality of the so called chemical/physical based approach will be discussed. Furthermore application examples will be presented which shows the different ways in which SCR modeling is used at DaimlerChrysler.