Transactions of the Korean Society of Automotive Engineers (한국자동차공학회논문집)

The Korean Society of Automotive Engineers (한국자동차공학회)
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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

급가감속 운전에 따른 듀얼 모노리스형 촉매변환기 내의 유동 균일도와 압력 강하에 관한 수치적 연구

  • 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)
  • 김영득 (한양대학교 기계공학과 대학원) ;
  • 정수진 (자동차부품연구원) ;
  • 김우승 (한양대학교 기계공학과)
  • Published : 2007.09.01
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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

References

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