스파크점화기관에서 흡기제어 방식이 부분부하 성능에 미치는 영향(1) - 스로틀링과 마스킹의 비교 (Effect of Intake Flow Control Method on Part Load Performance in SI Engine(1) - Comparison of Throttling and Masking)

서지정보

· 발행기관 : 한국자동차공학회
· 수록지 정보 : 한국자동차공학회 논문집 / 22권 / 2호 / 156 ~ 165페이지
· 저자명 : 강민균, 엄인용

초록

This paper is the first investigation on the effect of flow control methods on the part load performance in aspark ignition engine. For comparison of the methods, two control devices, port throttling and masking, were applied toa conventional engine without any design change of the intake port. Steady flow evaluation shows that steady flow ratesper unit opening area and swirl ratio are very low compared with the port throttling and saturated from mid-stage valvelift, however, swirl increases slightly as the lift is higher in case of 1/4 masking control. In the part load performance,the effect of simple port throttling on lean misfire limit expansion is limited and insufficient; on the other hand amasking improves the limit considerably without any port modification for increasing swirl. Also the results show thatthe intake flow control improves the combustion with following two mechanisms: stratification induced by thecombination of the flow pattern and the fuel injection timing attribute to ignition ability and the intensified flow ensurefast burn. In addition fuel consumption reduces under the flow controls and the reduction rate is different according tothe operation conditions and control methods. At the Stoichiometric and/or low speed and low load the throttlingmethod is more advantageous; however vice versa at lean and high load condition. Finally, the throttling is moreefficient for HC reduction than masking, on the other side the NOx emissions increase under the masking and decreaseunder the port throttling compared with conventional port scheme.

영어초록

This paper is the first investigation on the effect of flow control methods on the part load performance in aspark ignition engine. For comparison of the methods, two control devices, port throttling and masking, were applied toa conventional engine without any design change of the intake port. Steady flow evaluation shows that steady flow ratesper unit opening area and swirl ratio are very low compared with the port throttling and saturated from mid-stage valvelift, however, swirl increases slightly as the lift is higher in case of 1/4 masking control. In the part load performance,the effect of simple port throttling on lean misfire limit expansion is limited and insufficient; on the other hand amasking improves the limit considerably without any port modification for increasing swirl. Also the results show thatthe intake flow control improves the combustion with following two mechanisms: stratification induced by thecombination of the flow pattern and the fuel injection timing attribute to ignition ability and the intensified flow ensurefast burn. In addition fuel consumption reduces under the flow controls and the reduction rate is different according tothe operation conditions and control methods. At the Stoichiometric and/or low speed and low load the throttlingmethod is more advantageous; however vice versa at lean and high load condition. Finally, the throttling is moreefficient for HC reduction than masking, on the other side the NOx emissions increase under the masking and decreaseunder the port throttling compared with conventional port scheme.

참고자료

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