均质充量压燃发动机着火过程控制参数的研究

Study on the Control of HCCI Ignition by Controls Parameters

为了研究均质充量压缩火燃烧(Homogeneous Charge Compression Ignition,HCCI)发动机在不同燃料下的着火控制时刻影响因素,以甲烷/丙烷混和物和异辛烷/正庚烷混合物作为燃料,考察了十六烷值、辛烷值、压缩比、燃空当量比、进气温度、进气压力对HCCI发动机着火时刻的影响。计算结果表明,随着燃料十六烷值的增加,着火延迟期减小;随着燃料辛烷值的增加,着火延迟期增加。而压缩比,燃空当量比,进气温度的变化会引起燃料着火时刻的显著变化。进气压力的变化对高十六烷值的燃料着火延迟期影响较小,但对辛烷值高的气体燃料着火延迟期有一定影响。综合来说,气体十六烷值越低,辛烷值越大,着火延迟期受上述参数变化影响越大。

Using two kinds of mixture as fuel, the influence of cetane number, octane number, compression ratio, equivalence ratio and intake charge temperature in the ignition process of HCCI engine has been evaluated. The results indicate that the ignition delays of combustion increase with the increase of the octane number and the decrease of the cetane number. The start of ignition is strongly affected by fuel structure and the running conditions of the simulate engine. The changes of the compression ratio, equivalence ratio, and initial temperature will bring on distinct change of the ignition of combustion. The initial pressure has slighter influence on the ignition delay for the fuels with high cetane number compared with the high octane number fuels. In conclusion, the influence of the control parameters to the ignition delay is increased with the increase of the octane number and the decrease of the cetane number of the fuel.