封闭空间中易燃混合气体在HF和CO2激光作用下的燃烧引发

研究了封闭圆柱石英腔中化学计量CH4：O2混合气的燃烧试验。使用了非定域脉冲HF激光触发和直接使用脉冲CO2激光器助燃两种引燃方法。第二种引燃方法是使用小剂量的可以强烈吸收脉冲CO2激光辐射的sF6来加热易燃混合气。研究了燃烧过程,并确定了燃烧辉光的谱线特征。试验表明,即使在小体积反应器中,固定数量反应气的快速激光加热也能够极大地加速燃烧进程并达到混合气燃烧的爆炸模式。得到了阈值情况下沿腔轴的初始温度分布。

Combustion initiation of flammable gas mixture in a closed volume by high power HF and CO2 laser

The ignition of stoichiometric CH4∶O2 mixture in a closed cylindrical quartz chamber was investigated. Two methods of combustion initiation were used: mixture ignition by freely localized pulse HF laser produced laser spark and mixture ignition by direct gas heating with the help of a pulse CO2 laser. In the latter case, the small admixture of SF6 strongly absorbing CO2 laser radiation was used for pulse heating of flammable mixture. Dynamics of combustion was investigated and the spectral characteristics of combustion glow were determined.The experiment demonstrates that rapid laser heating of a certain amount of reactive gas can significantly accelerate the process of inflammation and can realize the detonation mode of combustion gas mixture,even in a small reactor volume. Initial gas temperature distributions along chamber axis for threshold conditions are obtained.