汽油机瞬态工况燃烧规律的数值研究

Numerical Study on Combustion Regularity of Gasoline Engine under Transient Conditions

为寻求PFI汽油机不同运转参数下缸内燃烧的规律,优化汽油机瞬态燃烧过程,在准维燃烧模型的基础上建立了汽油机瞬态双区燃烧模型,对汽油机缸内燃烧情况进行数值仿真。通过对比不同转速、点火提前角以及空燃比下缸内燃烧的情况,揭示了汽油机运转参数对缸内燃烧的影响规律。结果显示:较大的点火提前角以及较浓的混合气有利于发动机的燃烧,而较高的转速则不利于缸内的燃烧。

In order to find the regularity of combustion in the cylinder under different operating parameters of PFI gasoline engine, and optimize its transient combustion process, a transient dual-zone combustion model of gasoline engine was established based on the quasidimensional combustion model. And then a numerical simulation of combustion in the cylinder of gasoline engine is carried out. By comparing the combustion of the cylinder under different speed, ignition advance angle and air-fuel ratio, the influence of gasoline engine operating parameters on the combustion in the cylinder is revealed. The results show that： larger ignition advance angle and thicker mixture are conducive to the combustion of the engine, while a higher speed is not conducive to the combustion.