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Numerical Evaluation of a Radially Variable Cell Density Strategy for Improving Light-off Performance: Focusing on Light-off Catalyst  

정수진 (동해대학교 자동차공학과)
김우승 (한양대학교 기계공학과)
Publication Information
Transactions of the Korean Society of Automotive Engineers / v.10, no.1, 2002 , pp. 115-124 More about this Journal
Abstract
The optimum design of auto-catalyst needs a good compromise between the pressure drop and flow distribution in the monolith. One of the effective methods to achieve this goal is to use the concept of radially variable cell density. However, there has been no study of evaluating the usefulness of this method on light-off catalyst. We have computationally investigated the effectiveness of variable cell density technique applied to the light-off catalyst using a three-dimensional integrated CFD model. in which transient chemical reacting calculations are involved. Computed results show that variable cell density technique can reduce the accumulated emissions of CO and HC during the early 100sec of FTP cycle by 86.78 and 80.87%, respectively, The effect of air-gap between the monoliths has been also examined. It is found that air-gap has a beneficial effect on reducing pressure drop and cold-start emissions.
Keywords
Light-off catalyst; Variable cell density technique; Air-gap; Light-off;
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