[가솔린엔진] 활성화 성능향상을 위한 웜업 촉매변환기의 적용에 관한 3차원 수치 해석 연구

HC and CO emissions during the cold start contribute the majority of the total emissions in the legislated driving cycles. Therefore. in order to minimize cold start emissions. the fast light-off techniques have been developed and presented in the literature. This study numerically considers three-dimensional unsteady compressible reacting flow in the warm-up and main catalysts to examine the impact of a warm-up catalyst on thermal response of the main catalyst and tail pipe emission. The effect of flow distribution on temperature distribution and emission performance has also been investigated. The present results show that a thin reaction layer is located at the inlet of the warm-up catalyst and flow distribution has a great influence on the temperature distribution during the entire warm-up period.