激光诱导击穿火焰等离子体光谱研究

采用PI-MAX-II型增强型电荷耦合器件, 用Nd:YAG纳秒脉冲激光器输出的1064 nm强光束击穿在一个大气压的空气中燃烧的酒精灯火焰, 对激光诱导击穿酒精灯火焰产生的等离子体光谱进行了初步研究. 根据美国国家标准与技术研究院原子发射谱线数据库, 对等离子体中的主要元素的特征谱线进行了标识和归属. 通过激光诱导击穿空气等离子体光谱、激光诱导击穿酒精灯火焰等离子体光谱、激光诱导酒精喷灯火焰等离子体光谱的对比分析, 发现不同燃烧状况下的光谱中各原子谱线的相对强度是不同的. 这些结果对于使用激光诱导击穿技术分析和研究碳氢燃料在空气中的燃烧特性具有重要的意义和参考价值, 同时也为将该技术应用于燃烧诊断提供了实验依据.

Spectroscopic study on the laser-induced breakdown flame plasma

The emission spectra from a flame-breakdown atmospheric pressure plasma generated by a nanosecond pulsed 1064 nm beam of Nd:YAG laser are investigated by using a PI-MAX-II intensified charge coupled device. The emission lines of the main elements, such as carbon, hydrogen, oxygen and nitrogen are identified according to the national institute of standards and technology database of atomic emission. It is found that the relative intensities of the atomic emission lines are different from each other under different combustion conditions by making a comparative analysis of the spectra of laser induced breakdown air plasma, alcohol burner flame plasma, and alcohol blast burner flame plasma. The obtained results in this work provide an experimental basis for applying the laser-induced breakdown technology to the combustion diagnostics, and have an important reference and significance for analyzing the characteristics of hydrocarbon fuel combusting in air.