Three-Way Catalytic Converter Modeling as a Modern Engineering Design Tool

The competition to deliver ultra low emitting vehicles at a reasonable cost is driving the automotive industry to invest significant manpower and test lab resources in the design optimization of increasingly complex exhaust aftertreatment systems. Optimization can no longer be based on traditional approaches, which are intensive in hardware use and lab testing. This paper discusses the extents and limitations of applicability of state-of-the-art mathematical models of catalytic converter performance. In-house software from the authors' lab, already in use during the last decade in design optimization studies, updated with recent, important model improvements, is employed as a reference in this discussion. Emphasis is on the engineering methodology of the computational tools and their application, which covers quality assurance of input data, advanced parameter estimation procedures, and a suggested performance measure that drives the parameter estimation code to optimum results and also allows a less subjective assessment of model prediction accuracy. Extensive comparisons between measured and computed instantaneous emissions overfull cycles are presented, aiming to give a good picture of the capabilities of state of the art engineering models of automotive catalytic converter systems.

[1]  James C. Cavendish,et al.  Mathematical modeling of catalytic converter lightoff. Part III: Prediction of vehicle exhaust emissions and parametric analysis , 1985 .

[2]  S. E. Voltz,et al.  Kinetic Study of Carbon Monoxide and Propylene Oxidation on Platinum Catalysts , 1973 .

[3]  Daniel Schweich,et al.  Three-way monolithic converter: Simulations versus experiments , 1996 .

[4]  M. Sheintuch,et al.  Modeling and analysis of spatiotemporal oscillatory patterns during CO oxidation in the catalytic converter , 2000 .

[5]  J. Schmidt,et al.  The Impact of High Cell Density Ceramic Substrates and Washcoat Properties on the Catalytic Activity of Three Way Catalysts , 1999 .

[6]  Douglas M. Bates,et al.  Nonlinear Regression Analysis and Its Applications , 1988 .

[7]  Luigi Glielmo,et al.  A Two-Time-Scale Infinite-Adsorption Model of Three Way Catalytic Converters During the Warm-Up Phase , 2001 .

[8]  Anastassios M. Stamatelos,et al.  Development and application range of mathematical models for 3-way catalytic converters , 1997 .

[9]  Kyriacos Zygourakis,et al.  Transient operation of monolith catalytic converters: a two-dimensional reactor model and the effects of radially nonuniform flow distributions , 1989 .

[10]  David G. Luenberger,et al.  Linear and Nonlinear Programming: Second Edition , 2003 .

[11]  Gbmm Guy Marin,et al.  Competing reactions in three-way catalytic converters : modelling of the NOx conversion maximum in the light-off curves under net oxidising conditions , 2000 .

[12]  David L. Van Ostrom,et al.  A Three-Dimensional Model for the Analysis of Transient Thermal and Conversion Characteristics of Monolithic Catalytic Converters , 1988 .

[13]  I. Kandylas,et al.  Computergestützter Entwurf von Abgas-Nachbehandlungskonzepten , 1999 .

[14]  E. Koberstein,et al.  The A/F Window with Three-Way Catalysts. Kinetic and Surface Investigations. , 1987 .

[15]  David G. Luenberger,et al.  Linear and nonlinear programming , 1984 .

[16]  Costas Papadimitriou,et al.  KINETIC PARAMETER ESTIMATION BY STANDARD OPTIMIZATION METHODS IN CATALYTIC CONVERTER MODELING , 2004 .

[17]  Anastassios M. Stamatelos,et al.  Quality assurance of exhaust emissions test data , 2004 .

[18]  Steffen Tischer,et al.  Transient three-dimensional simulations of a catalytic combustion monolith using detailed models for heterogeneous and homogeneous reactions and transport phenomena , 2001 .

[19]  Anastassios M. Stamatelos,et al.  The role of computer aided engineering in the design optimization of exhaust after-treatment systems , 1998 .

[20]  Emanuel Falkenauer,et al.  Genetic Algorithms and Grouping Problems , 1998 .

[21]  Anastassios M. Stamatelos,et al.  Computer aided assessment and optimization of catalyst fast light-off techniques , 1997 .

[22]  Anastassios M. Stamatelos,et al.  Mathematical modelling of catalytic exhaust systems for EURO-3 and EURO-4 emissions standards , 2001 .

[23]  Grigorios C. Koltsakis,et al.  CATALYTIC AUTOMOTIVE EXHAUST AFTERTREATMENT , 1997 .

[24]  Robert E. Hayes,et al.  MASS AND HEAT TRANSFER EFFECTS IN CATALYTIC MONOLITH REACTORS , 1994 .

[25]  Bruce A. Finlayson,et al.  Mathematical models of the monolith catalytic converter: Part I. Development of model and application of orthogonal collocation , 1976 .

[26]  Scott C. Williams,et al.  Modeling current generation catalytic converters: laboratory experiments and kinetic parameter optimization. Steady state kinetics , 1992 .

[27]  S. Wakamatsu,et al.  Peculiarities of volatile hydrocarbon emissions from several types of vehicles in Japan , 2001 .

[28]  Dalimil Šnita,et al.  3-D modeling of monolith reactors , 1997 .

[29]  Anastassios M. Stamatelos,et al.  Transient Modeling of 3-Way Catalytic Converters , 1994 .

[30]  Tariq Shamim,et al.  A Comprehensive Model to Predict Three-Way Catalytic Converter Performance , 2002 .

[31]  James C. Cavendish,et al.  Transients of monolithic catalytic converters. Response to step changes in feedstream temperature as related to controlling automobile emissions , 1982 .

[32]  Daniel Schweich,et al.  Three-way catalytic converter modelling. Numerical determination of kinetic data , 1998 .

[33]  James C. Cavendish,et al.  Mathematical modeling of catalytic converter lightoff. Part II: Model verification by engine‐dynamometer experiments , 1985 .

[34]  R. Farrauto,et al.  Catalytic converters: state of the art and perspectives , 1999 .

[35]  Michel Prigent,et al.  Three-way catalytic converter modelling: fast- and slow-oxidizing hydrocarbons, inhibiting species, and steam-reforming reaction , 1998 .

[36]  James Wei,et al.  Mathematical modeling of monolithic catalysts , 1976 .

[37]  David E. Goldberg,et al.  Genetic Algorithms in Search Optimization and Machine Learning , 1988 .

[38]  R. Aris,et al.  Multiple oxidation reactions and diffusion in the catalytic layer of monolith reactors , 1983 .

[39]  Γεώργιος Ποντικάκης,et al.  Modeling, reaction schemes and kinetic parameter estimation in automotive catalytic converters and diesel particulate filters , 2003 .