激光感生击穿光谱技术在燃烧诊断中的应用

Application of Laser-Induced Breakdown Spectroscopy to Combustion Diagnosis

简述了激光感生击穿光谱(LIBS)技术的研究基础,包括实验台架、光谱定性定量分析方法,详细介绍了所进行的LIBS技术在燃烧诊断中的应用研究工作,利用LIBS技术对飞灰中的碳含量和燃煤特性及成分进行了分析.结果表明,采用LIBS测得的飞灰含碳量与传统的重量燃烧法测得的飞灰含碳量结果吻合较好;煤化程度不同的煤呈现出不同的等离子体时间谱,在相同实验条件下,煤化程度越高的煤种其等离子体温度越高;利用LIBS技术测得的燃煤成分含量与传统测量方法得到的结果吻合亦较好.该研究证实了激光感生击穿光谱技术在燃烧诊断中应用的可行性,为后续的燃烧诊断研究和试验工作奠定了基础.

In this paper, fundamentals of laser-induced breakdown spectroscopy （LIBS） studies are briefly reviewed first, including the experimental set-up, the qualitative and quantitative analysis methods for the spectrum. Then, the studies on combustion diagnosis by LIBS are introduced in detail. Moreover, a quantitative analysis of residual carbon in fly ash is carried out, and the characteristics and composition of coal are finally analyzed. The results show that （1） the carbon content in fly ash measured by LIBS accords well with that measured by the traditional method of Weight-Combustion; （2） the coal samples with different coalification degrees show different plasma time-resolved spectral characteristics; （3） in the same experimental conditions, the plasma temperature increases with the coalification degree; and （4） the coal content measured by LIBS coincides with that measured by the traditional method. The present study verifies the feasibility of combustion diagnosis by LIBS and lays a foundation for further studies and experiments of combustion diagnosis.