This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Computer Application in Converter Development from Concept to Manufacturing
ISSN: 0148-7191, e-ISSN: 2688-3627
Published November 01, 2001 by The Automotive Research Association of India in India
Annotation ability available
Event: SIAT 2001
Conventional catalytic converter developments driven by trial and error attempts by experts who successfully employ heuristics (a set of empirical rules gained through time and experience) will not be able to meet the current demanding needs. The cost and time involved in testing every catalytic converter mandates new approaches aimed at improving efficiency and reducing development lead time.
Computational tools such as HeatCad, P-Cat, CatHeat, WAVE, Computational Fluid Dynamics (CFD), Finite Element Analysis (FEA) and Monte-Carlo simulation are sequentially applied to design, optimize and manufacture catalytic converter. Heatcad analysis provides the way to identify thermal management issues and to optimize runner lengths and material thickness of the manifold, and downpipes. P-Cat is used to estimate back pressure due to substrates, washcoat, end cones, and inlet/outlet pipes. CatHeat analysis is used to predict the temperature profile across the converter. CatHeat offers input for the selection of the right insulation material and mounting gap to comply with durability and external skin temperature requirements. Computational Fluid Dynamics (CFD) analysis is used to design the converter cone geometry and downpipe orientation to obtain uniform exhaust gas flow to achieve maximum converter performance and reduce mat erosion. The uniformity index, velocity index (eccentricity) and pressure drop index predicted are used to optimize the geometry and orientation of the converter components. WAVE simulation is used to predict the exhaust system back pressure from the engine headface to tail pipe and to estimate engine performance. Finite Element Analysis (FEA) is used to predict structural mechanics and structural dynamics of the full exhaust system to give insight about the thermal fatigueness of the converter assembly. Heat transfer analysis performed with thermal, mechanical and road load conditions is used to predict the static and vibrational stresses of the converter components. Monte-Carlo simulation is used to study the effect of substrate, mounting mat and converter shell dimensional tolerances on the converter manufacturing process. Improvements ranging from 28% and 64% in GBD control was achieved.
CitationRajadurai, S., "Computer Application in Converter Development from Concept to Manufacturing," SAE Technical Paper 2001-28-0046, 2001, https://doi.org/10.4271/2001-28-0046.
- Rajadurai, S. Geer. L. Chung, H. Snider, B. Carlson, T. Michels, J. “Shoebox Converter design for thinwall ceramic substrates” SAE 1999-01-1542
- Rajadurai, S. Geer. L. Chung, H. Chang, H. Pan, F. “Catalytic Converter Design, Development and Optimization using Computational analysis and Engineering” SAE 990050 1999
- Ryan, M.J. Becker, E.R. Zygourakis, K. “light-off performance of catalytic converters, The effect of heat / mass transfer characteristics,” SAE 910610
- Ten Eyck John D. “Monolithic catalytic converter mounting arrangement,” Sep. 5 1989
- Robertson, D.F. “A study of thermal energy conservation in exhaust pipes,” SAE 790307 1979
- Wendland, D. W. “Automotive exhaust system steady state heat transfer,” SAE 931085 1993
- Chen, D. K. S. “A numerical model for thermal problems in exhaust systems,’ SAE 931070
- Incropera, F. P. Dewitt, D. P. Fundamnetals of heat and mass transfer Third John Wiley & Sons 1990
- Ball, D. J. “Distribution of warm-up and underfloor catalyst volumes,” SAE 922338 San Francisco, California 1992
- Zucrow, M. J. Hoffman, J. D. “Gas Dynamics,” 1 John Wiley and Sons 1976
- Bressler, H. Rammoser, D. Neumaier, H. Terres. F. “Experimental and predictive investigation of a close coupled converter with pulsating flow,” SAE 960564 1996
- Meissner L.P. Organick E.I. “Fortran 77: Featuring Structured Programming,” Addison-Wesley Series in Computer Science 334 335 1982
- Kalos M.H. Whitlock P.A. “Monte-Carlo Methods,” Whiley-Interscience 48 1986
- Tagamori, M Rajadurai, S. “Catalytic converter design for manufacturing using Maonte-carlo simulation”