A Combined 3D/Lumped Modeling Approach to Ammonia SCR After-treatment Systems: Application to Mixer Designs 2006-01-0469
In practical applications of ammonia SCR aftertreatment systems using urea as the reductant storage compound, one major difficulty is the often constrained packaging envelope. As a consequence, complete mixing of the urea solution into the exhaust gas stream as well as uniform flow and reductant distribution profiles across the catalyst inlet face are difficult to achieve.
This paper discusses a modeling approach, where a combination of 3D CFD and a lumped parameter SCR model enables the prediction of system performance, even with non-uniform exhaust flow and ammonia distribution profiles. From the urea injection nozzle to SCR catalyst exit, each step in the modeling process is described and validated individually. Finally the modeling approach was applied to a design study where the performance of a range of urea-exhaust gas mixing sections was evaluated.
The application to the design study shows that this combination of tools, CFD and lumped parameter SCR model, gives accurate predictions of the effects of design changes to the actual hardware on the overall performance.
Citation: Karlsson, M., Wallin, U., Fredholm, S., Jansson, J. et al., "A Combined 3D/Lumped Modeling Approach to Ammonia SCR After-treatment Systems: Application to Mixer Designs," SAE Technical Paper 2006-01-0469, 2006, https://doi.org/10.4271/2006-01-0469. Download Citation
Mikael Karlsson, Ulf Wallin, Sten Fredholm, Jonas Jansson, Gert-Ove Wahlström, Christoph M. Schär, Christopher H. Onder, Lino Guzzella
Swenox AB, Volvo Powertrain Corporation, Measurement and Control Laboratory, Swiss Federal Institute of Technology (ETH)
SAE 2006 World Congress & Exhibition
Diesel Exhaust Emission Control Modeling 2006-SP-2023