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缸内直接喷射式汽油机的一个显著特点是依靠火花塞点燃喷入缸内的汽油油束。由于缸内混合气浓度极不均匀，所以其点火及火焰传播过程与普通均质燃烧式发动机有很大的不同。火焰核心的稳定形成及初始火焰发展对缸内的整个燃烧过程有极其重要的影响。本文利用二维两相混合模型模拟喷雾过程，利用一个详细的准维模型模拟火花塞的点火过程，并采用特殊处理方法使两个子模型相匹配，计算了缸内直接喷射式汽油机从喷雾到形成稳定火核的全过程，分析了多种因素对点火稳定性的影响，尤其是对涡流比、点火时刻和喷油定时之间的适当配合进行了模拟分析。计算结果对优化实验有明显的指导作用。
A notable feature of a direct injection gasoline engine in a cylinder is the ignition of a gasoline jet that is injected into the cylinder by means of a spark plug. Due to the extremely uneven concentration of the mixture in the cylinder, the ignition and flame propagation processes are quite different from those of a conventional homogeneous combustion engine. The stable formation of the flame core and the development of the initial flame have an extremely important effect on the overall combustion process in the cylinder. In this paper, a two-dimensional two-phase hybrid model is used to simulate the spray process. A detailed quasi-dimensional model is used to simulate the ignition process of the spark plug. Matching the two submodels with a special treatment method, the calculation of the direct injection gasoline engine from spray to form a stable The whole process of the nucleus, analyzes the influence of many factors on the ignition stability, especially the proper matching between the eddy current ratio, the ignition timing and the injection timing. The calculation results have obvious guidance to optimize the experiment.