喷油压力对柴油机喷雾、混合及燃烧特性影响的数值模拟研究

The Numerical Simulation of Injection Pressure on Diesel Spray,Mixing and Combustion Characteristics

基于对某型直喷式柴油机缸内工作过程的多维数值模拟,研究了喷油压力对燃油喷雾特性、油气混合特性、燃烧特性及柴油机性能的影响规律。结果表明:提高喷油压力,喷雾粒度越细,燃油蒸发速度加快,油气混合的速度和均匀度均得到改善,缩短了燃烧持续期,提高了循环热效率,但是平均压力升高率呈线性增加,影响工作过程的稳定性。

Based on the muhi-dimensional numerical simulations of DI diesel engine working process, the law of injection pressure on fuel spray characteristics, mixing characteristics, combustion characteristics and engine performance were investigated. The results showed that： Through increasing injection pressure, the spray particle size is reduced, fuel evaporation rale is increased, mixing rate and uniformity are improved, the combustion duration is reduced, and thermal efficiency is improved. But the average pressure rise rate linearly increased, and the stability of the work process is affected.