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An Numerical Study on the Flow Uniformity and Pressure Drop in Dual Monolith Catalytic Converter during the Rapid Acceleration/Deceleration Driving  

Kim, Young-Deuk (Department of Mechanical Engineering, Hanyang University)
Jeong, Soo-Jin (Advanced Power & IT Research Center, Korea Automotive Technology Institute)
Kim, Woo-Seung (Department of Mechanical Engineering, Hanyang University)
Publication Information
Transactions of the Korean Society of Automotive Engineers / v.15, no.5, 2007 , pp. 63-71 More about this Journal
Abstract
The conversion efficiency, durability and pressure drop of the automotive exhaust catalysts are dependent on the flow distribution within the substrate. Conventional porous medium approaches assuming monolith resistance based on the one-dimensional laminar flow for simulating the flow through the automotive exhaust catalysts over-predict the flow uniformity in the monolith. In this study, additional pressure loss is also considered by accounting for entrance effects due to the oblique flow incident on the front face of monolith as a consequence of flow separation and recirculation within the diffuser. The incorporation of an additional pressure loss improves the predictions for the maximum flow velocity within the substrate. An numerical study has also been conducted for the three-dimensional unsteady incompressible non-reacting flow inside various dual-monolith catalytic converters for the rapid acceleration/deceleration driving.
Keywords
Dual monolith catalytic converter; Uniformity index; Pressure drop; Diffuser angle; Air-gap length;
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  • Reference
1 A. J. Baxendale, 'Computational Fluid Dynamics in Exhaust System Design and Development,' SAE 931072, 1993
2 H. Weltens, H. Bressler, F. Terres, H. Neumaier and D. Rammoser, 'Optimisation of Catalytic Converter Gas Flow Distribution by CFD Predictions,' SAE 930780, 1993
3 J. Wollin and S. F. Benjamin, 'A Study of the Flow Performance of Ceramic Contoured Substrates for Automotive Exhaust Catalyst Systems,' SAE 993626, 1999
4 S. F. Benjamin, R. J. Clarkson, N. Haimad and N. S. Girgis, 'An Experimental and Predictive Study of the Flow Field in Axisymmetric Automotive Exhaust Catalyst Systems,' SAE 961208, 1996
5 S. J. Jeong, W. S. Kim, I. T. Im, N. J. Choi and J. H. Lee, 'Evaluation of Numerical Models for the Flow Maldistribution and Pressure Drop through Automotive Catalytic Converter,' International Conference for Mechanical and Automotive Technologies, pp.145-149, 2005
6 E. H. Lee, C. K. Lee, J. S. Yoo and J. H. Lee, 'A Study on the Fluid Flow Characteristic in Catalytic Converter for Various Inlet and Outlet Header Shapes,' Transactions of KSAE, Vol.7, No.7, pp.187-194, 1999
7 S. J. Jeong and W. S. Kim, 'Three-Dimensional Flow Analysis of Catalytic Converter for Reducing Emission,' Transactions of KSAE, Vol.6, No.5, pp.55-65, 1998
8 K. Umehara, T. Yamada, T. Hijikata, Y. Itchikawa and F. Katsube, 'Advanced Ceramic Substrate: Catalytic Performance Improvement by High Geometric Surface Area and Low Heat Capacity,' SAE 971029, 1997
9 S. F. Benjamin, N. Haimad, C. A. Roberts and J. Wollin, 'Modelling the Flow Distribution through Automotive Catalytic Converters,' Proc. Instn. Mech. Engrs, Vol.215, Part C, pp.379-383, 2001
10 M. C. Lai and J. Y. Kim, 'Three-dimensional Simulations of Automotive Catalytic Converter Internal Flow,' SAE 910200, 1991
11 STAR-CD User Manual, 2004
12 S. J. Jeong and W. S. Kim, 'Three Dimensional Unsteady Flow Characteristics inside the Catalytic Converter of 6 Cylinder Gasoline Engine,' Transactions of KSAE, Vol.6, No.4, pp.108-120, 1998
13 A. Heibel and M. A. A. Spaid, 'A New Converter Concept Providing Improved Flow Distribution and Space Utilization,' SAE 990768, 1999
14 J. Y. Kim, 'Flow Distribution and Pressure Drop in Diffuser-Monolith Flow: Implications to the Automotive Catalytic Converter Design,' Ph. D. Dissertation, Wayne State University, Detroit, Michigan, 1993
15 T. Hauber, P. Zacke, J. Braun and D. Ueberschär, 'Influence of the Space between Monoliths and the Geometry of Endcones on the Conversion Rate of a Catalytic Converter,' SAE 980424, 1998