柴油/甲醇组合发动机燃烧压力特性研究

采用柴油/甲醇组合燃烧(DMCC)方式对增压共轨发动机进行缸内燃烧压力特性研究。对比分析了DMCC模式和纯柴油模式下的缸内燃烧压力、压力升高率、最高燃烧压力和燃烧放热率。结果表明:DMCC模式大大改变了放热率的形式,使得着火始点较原机推迟很多;并且燃烧过程中的预混燃烧比例明显加大,扩散燃烧的比例减少。该研究结果为大幅度提高柴油机效率、减少有害气体排放提供了理论依据。

Investigation of Combustion Pressure Characteristics from Diesel Engine with DMCC Mode

The combustion pressure characteristics of a turbocharged common rail diesel engine were experimentally investigated when using diesel/methanol compound combustion mode (DMCC). The combustion pressure characteristics were compared with the baseline engine, which including the related parameters such as the combustion pressure, the rate of pressure rise, maximum combustion pressure and combustion heat release rate. The results showed that, compared with the baseline engine, the form of heat release rate was changed significantly with DMCC mode, and the ignition point was simultaneously delayed a lot. Besides, the proportion of premixed combustion increased, and the proportion of diffusion combustion decreased. The results provided the theoretical basis for improving the efficiency and reducing the exhaust emissions of diesel engine by the DMCC mode.