氢气定容燃烧的实验研究

利用定容燃烧弹和高速数据采集系统对氢气定容燃烧进行实验研究，得出氢气定容燃烧压力变化过程、燃烧爆压及爆炸常数的变化规律。研究结果表明:中心点火定容燃烧的压力变化过程为:从开始的火花跳火干扰到平稳的等压燃烧，再到压力的慢速和快速增加，在燃烧的中后期会出现压力振荡；在非燃烧极限工况下，随着燃空当量比的增加燃烧爆压先增加后减小，随着初始压力的升高燃烧爆压几乎线性增加，随着温度的增加燃烧爆压和最大燃烧爆压都减小；随着燃空当量比的增加爆炸常数先增加后减小，在燃空当量比小于4.0的工况，燃烧爆炸常数随初始压力的升高而增加，而燃空当量比大于4.0的工况随着初始压力的升高而下降；在燃空当量比小于2.5时，燃烧爆炸常数随温度升高而减小，在燃空当量比大于2.5时，则正好相反。

Experimental study on hydrogen constant volume combustion

Hydrogen constant volume combustion was investigated by using a constant volume combustion bomb and a high－speed data acquisition system.The pressure change in the hydrogen constant volume combustion bomb was summarized and the rules of the combustion－explosion pressure and the explosion constant were generalized.The combustion pressure changing in the constant volume bomb with central ignition can be described in the following process.The combustion which was interfered by ignition was at a constant pressure, the pressure increased slowly at first, and then increased rapidly during the combustion.There would be a pressure oscillation in the later half stage of the combustion.If it was not under the extreme conditions, the explosion peak pressure increased firstly and then decreased with the fuel equivalence ratio increasing.There was almost a linear relation between the initial pressure and the peak pressure.The explosion pressure and peak pressure decreased with the initial temperature increasing.The explosion constant increased firstly and then decreased with the fuel equivalence ratio increasing, too.When the fuel equivalence ratio was lower than 4, the explosion constant increased with the initial pressure increasing, or vice versa.When the fuel equivalence ratio was lower than 2.5, the explosion constant decreased with the temperature increasing.And when the fuel equivalence ratio was higher than 2.5, it was just the opposite.