基于 CONVERGE 3.0 软件建立了柴油机燃烧室的三维计算流体力学（computational fluid dynamics, CFD）模型，并耦合 CHEMKIN 程序中包含 182 个反应和 52 个组分的化学动力学机理。采用该模型研究了喷油夹角对甲醇柴油混合燃料发动机缸内压力、温度及排放特性的影响。结果显示，当喷油夹角θ=60° 时，油束轴线更靠近燃烧室凸台，大量燃油在凸台表面聚集，混合气形成效果较差，导致Soot生成增加；而在 θ=75° 条件下，油气混合更为均匀，缸内峰值压力与温度均达到最大值。随着喷油夹角进一步增大，NOx与N2O排放先升高后降低，均出现明显拐点，HCHO排放则呈持续下降趋势。

A three-dimensional computational fluid dynamics (CFD) model of a diesel engine combustion chamber was developed using CONVERGE 3.0 software, with coupling to a detailed chemical kinetic mechanism containing 182 reactions and 52 components implemented in the CHEMKIN program. The model was employed to investigate the effect of injection angle on in-cylinder pressure, temperature and emission characteristic in a methanol-diesel mixed fuel engine. The results showed that the fuel jet axis was oriented closer to the combustion chamber boss at the injection angle θ=60°, leading to substantial fuel accumulation on the piston bowl surface. This resulted in suboptimal air-fuel mixing and promoted soot formation due to locally rich mixtures. In contrast, improved spatial distribution of the fuel spray enhanced mixture homogeneity under the condition of θ=75°, resulting in more complete combustion and peak in-cylinder pressure and temperature values. As the injection angle increased further, NOx and N2 emissions first increased and then decreased, and showed obvious inflection points. Meanwhile, HCHO emissions showed a continuous downward trend.