【摘要】 利用发动机热力循环软件BOC9ST耦合嵌入详细化学反应动力学机理的CHEMKIN代码建立了GDI-HCCI 发动机燃烧数值模型,对缸内直喷汽油机采用分段燃油喷射配合负气门重叠角控制缸内混合气化学组分、混合气浓度及温度历程的策略进行了实验验证及模拟分析．结果显示,加大负气门重叠角以及在此期间喷油可以产生燃油改质效果,缸内温度升高,使HCCI着火更容易控制．由此在保证NOx排放极低的同时循环波动明显减小,负荷稀限拓宽,燃油经济性改善．更多还原

【Abstract】 A GDI-HCCI engine model was developed by coupling the CHEMKIN code with AVL BOOST?engine cycle simulation code. HCCI combustion was experimentally investigated and simulation analysis was carried out in a 4-stroke gasoline direct injection (GDI) engine with variable negative valve overlap (NVO). By combining split direct injection (SDI) with NVO, the history of the mixture temperature and concentration, chemical species in-cylinder can be controlled flexibly. The results show that HCCI combustion rate and ignition timing can be controlled and HCCI operation range can be extended.更多还原