This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
CFD Study of Sensitivity Parameters in SCR NOx Reduction Modeling
Technical Paper
2014-01-2346
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
The Diesel engine combustion process results in harmful exhaust emissions, mainly composed of Particulate Matter (PM), Hydro Carbon (HC), Carbon monoxide (CO) and Nitrogen Oxides (NOx). Several technologies have been developed in the past decades to control these diesel emissions. One of the promising and well matured technology of reducing NOx is to implement Selective Catalytic Reduction (SCR) using ammonia (NH3) as the reducing agent. For an effective SCR system, the aqueous urea solutions should be fully decomposed into ammonia and it should be well distributed across the SCR. In the catalyst, all the ammonia is utilized for NOx reduction process. In the design stage, it is more viable to implement Computational Fluid Dynamics (CFD) for design iterations to determine an optimized SCR system based on SCR flow distribution. And in later stage, experimental test is required to predict the after-treatment system performance based on NOx reduction.
The SCR model predicts the NH3 formation from urea decomposition and it is quantified at the SCR inlet, whereas experimental data involves the NOx reduction process. In order to validate the numerical predictions, the modeling needs to include surface reactions happening in the SCR catalyst bed. There are many factors that affect NOx conversion process, such as exhaust temperature, NO2/NOx ratio, catalyst coating, oxidation, etc. To model SCR Kinetics, various input parameters are required and also the reaction process needs to be well defined. The objective of this work is to conduct urea SCR spray modeling studies to focus on these input parameters and to observe its influence over NOx reduction process.
Recommended Content
Authors
Topic
Citation
Sampath, M. and Lacin, F., "CFD Study of Sensitivity Parameters in SCR NOx Reduction Modeling," SAE Technical Paper 2014-01-2346, 2014, https://doi.org/10.4271/2014-01-2346.Also In
References
- Yim D.S. , Kim S.J. , Baik J.H. , Nam I. , Mok Y.S. , Lee J.W. , Cho B.K. , Oh S.H. Decomposition of Urea into NH3 for the SCR Process Ind.Eng.-Chem.Res. 43 1 2004 4856 4863
- Koebel M. , Elsener M. , Kleemann M. Urea-SCR: a promising technique to reduce NOx emissions from automotive diesel engines Catalysis Today 59 2000 335 345
- Schaber P.M. , Colson J. , Higgins S. , Dietz E. , Thielen D. , Anspach B. , Brauer J. Study of the urea thermal decomposition (pyrolysis) reaction and importance to cyanuric acid production American laboratory 1999
- Schaber P.M. , Colson J. , Higgins S. , Thielen D. , Anspach B. , Brauer J. Thermal decomposition (pyrolysis) of urea in an open reaction vessel Thermochimica Acta 424 2004 131 142
- Koebel M. , Elsener M. Journal of Chromatography A 689 1995 164 169
- Winkler , C. , Flörchinger , P. , Patil , M. , Gieshoff , J. et al. Modeling of SCR DeNOx Catalyst - Looking at the Impact of Substrate Attributes SAE Technical Paper 2003-01-0845 2003 10.4271/2003-01-0845
- Wurzenberger , J. and Wanker , R. Multi-Scale SCR Modeling, 1D Kinetic Analysis and 3D System Simulation SAE Technical Paper 2005-01-0948 2005 10.4271/2005-01-0948
- Blakeman , P. , Chandler , G. , John , G. , and Wilkins , A. Investigations into NOx Aftertreatment with Urea SCR for Light-Duty Diesel Vehicles SAE Technical Paper 2001-01-3624 2001 10.4271/2001-01-3624
- Dukowicz , J.K. A Particle-Fluid Numerical Model for Liquid Sprays J. Comp. Physics 35 229 253 1980
- Birkhold , F. Selektive katalytische Reduktion von Stickoxiden in Kraftfahrzeugen: Untersuchung der inspritzung von Harnstoffwasserlösung Dissertation Universität Karlsruhe 2007
- Birkhold , F. , Meingast , U. , Wassermann , P. , and Deutschmann , O. Analysis of the Injection of Urea-Water-Solution for Automotive SCR DeNOx-Systems: Modeling of Two-Phase Flow and Spray/Wall-Interaction SAE Technical Paper 2006-01-0643 2006 10.4271/2006-01-0643
- Birkhold , F. , Meingast , U. , Wassermann , P. and Deutschmann , O. Modeling and simulation of the injection of urea-water-solution for automotive SCR DeNOxsystems Applied Catalyst B Environmental 70 119 127 2007
- Kim , J. Y. , Ryu , S. H. and Ha , J. S. Numerical prediction of the characteristics of spray-induced mixing and thermal decomposition of urea solution in SCRsystems Proccedings of ICEF04 October 24 27 Long Beach, California USA
- O'Rourke , P. and Amsden , A. The Tab Method for Numerical Calculation of Spray Droplet Breakup SAE Technical Paper 872089 1987 10.4271/872089
- Gosman , A.D. and Ioannides , E. Aspects of Computer Simulation of Liquid- Fueled Combustors AIAA 81 323 1981
- Kuhnke D. Spray Wall Interaction Modeling by Dimensionless Data Analysis PhD thesis Technische Universität Darmstadt 2004
- Wruck N. W. Transientes Sieden von Tropfen beim Wandaufprall PhD thesis RWTH Aachen 1998
- Winkler , C. , Flörchinger , P. , Patil , M. , Gieshoff , J. et al. Modeling of SCR DeNOx Catalyst - Looking at the Impact of Substrate Attributes SAE Technical Paper 2003-01-0845 2003 10.4271/2003-01-0845
- Sampath , M. and Lacin , F. Role of CFD in Evaluating SCR NOx Reduction Performance Emission 2014