【摘要】 为验证被动预燃室技术在商用缸内直喷（gasoline direct injection, GDI）发动机中的应用潜力，采用三阶段喷射策略研究了预燃室点火发动机在增压稀薄燃烧环境中的热效率、燃烧特性（累计放热量达到总放热量的50%对应的曲轴转角CA50、爆震指数和循环变动系数）和排放特性，建立了三维仿真模型进行模拟。结果表明，在高负荷条件下，平均爆震指数可控制在0.20～0.34 MPa之间，循环变动系数可控制在3.0%～3.5%之间；当指示平均有效压力（indicated mean effective pressure, IMEP）在1.0 MPa～1.4 MPa范围内，指示热效率均能达到40%以上；负荷增加时，氮氧化物呈下降趋势，碳氢化合物和一氧化碳排放略有增加。更多还原

【Abstract】 To validate the potential application of passive pre-chamber technology in commercial gasoline direct injection(GDI) engines, a three-stage injection strategy was employed to investigate the thermal efficiency, combustion characteristics(crank angle corresponding to 50% cumulative heat release, knock index, and coefficient of variation), and emission characteristics of pre-chamber ignition engines in a boosted lean-burn environment. A three-dimensional simulation model was established to simulate the combustion and emission processes under different operating conditions. The results show that under high-load conditions, the average knock index could be controlled between 0. 20 and 0. 34 MPa, and the coefficient of variation could be maintained between 3. 0% and 3. 5%. Within the load range of(indicated mean effective pressure, IMEP) from 1. 0 MPa to 1. 4 MPa, all the indicated thermal efficiencies exceeded 40%. As the load increased, nitrogen oxides decreased, while hydrocarbon and carbon monoxide emissions slightly increased.更多还原