氢气体积分数对预混层流天然气火焰离子电流特性的影响

Effect of Hydrogen Volume Fraction on the Flame Ion Current Characteristics of Premixed Laminar Natural Gas

利用定容燃烧弹,结合离子电流采集系统和高速摄影系统,研究了天然气掺氢气预混层流火焰离子电流特性。通过试验获得了不同氢气体积分数下火焰的离子电流和燃烧室压力数据,同时利用纹影仪和高速摄影系统拍摄了火焰的传播图像;将离子电流波形特征参数与火焰纹影图片相结合,分析了氢气体积分数的增加对离子电流波形特征的影响。研究结果表明:随着氢气体积分数的增加,离子电流第一波峰和第二波峰的振幅增大,第一波峰出现时刻提前,第二波峰出现时刻推迟,从第一波峰到达第二波峰的时间延长;随着离子电流第二波峰到达时刻的延迟,离子电流第二波峰与燃烧室压力峰值的对应关系发生改变。

In this paper,the ion current characteristics of the premixed laminar flame of natural gas mixed with hydrogen are studied by using the constant volume combustion bomb combined with the ion current acquisition system and the high-speed photography system.The data of the ion current and combustion chamber pressure of combustion flame under different hydrogen volume fractions have been obtained by experiments,and the flame propagation images have been taken by the schlieren high-speed photography system at the same time,the effect of the increase of hydrogen volume fraction on the ion current waveform characteristic are analyzed by combining the characteristic parameters of ion current waveform with the flame schlieren image.The experimental study results show that as the volume fraction of hydrogen increases,the amplitudes of the first and second peaks of the ion current increase,the first peak appears earlier,the second peak appears later,and the duration of the ion current increases;with the delay of arrival time of the second peak,the correspondence between the pressure peak timing and the second peak timing of ion current is also changed.