HCCI엔진연소의 압력상승률 저감의 메카니즘에 대한 이해

다국어 초록 (Multilingual Abstract)

HCCI engine is able to achieve low NOx and particulate emissions as well as high efficiency. However, its operation range is limited by the knocking at high load, which results from an excessive . To solve the knocking problem, the PRR must be reduced, and stratified charge has been suggested. It is the method to disperse the auto-ignition timing at each local gas in combustion chamber by using thermal, mixing and stratifications. The purpose of this study is to investigate the mechanism and potential of stratified charge for reducing PRR on HCCI combustion. The numerical calculation with multi-zones model is run to know the potential of stratified charge for reducing PRR. DME is used as a fuel. As a result, following conclusions were obtained. 1) Stratified charge makes the gas temperature difference before reaction start by the differences of initial gas temperature, equivalence ratio and EGR ratio. As a result, the PRR reduction is occurred by the difference of reaction start timing. 2) gain the PRR reduction effect of 50%, temperature difference of 20K in case of thermal stratification, equivalence ratio difference of 0.16 in case of mixing stratification, EGR ratio difference of 15% in case of EGR stratification are needed. 3) When thermal, mixing and EGR stratifications are combined, “in case of relatively rich mixture with high temperature and relatively lean mixture with low temperature” and “in case of relatively rich EGR with low temperature and relatively lean EGR with high temperature” show the greatest potential for reducing PRR.

목차 (Table of Contents)

• Abstract
• 1. 서론
• 2. 화학반응계산
• 3. 계산결과
• 4. 결론
• 후기
• References