Temperature and Chemical Reaction Distribution of a Laminar Diffusion Flame Measured by X-ray Compton Scattering

A laminar diffusion flame was measured by X-ray Compton scattering. The temperature distribution was measured from an analysis of Compton scattered X-ray intensity. The chemical state distribution was obtained from a Compton scattered X-ray spectrum analysis (s-parameter analysis). The analysis of intensity and s-parameter of Compton scattered X-ray spectra indicate that the propane molecule emitted from the cylindrical Bunsen burner collapse immediately coincides with soot generation. Furthermore, the temperature increases up to 1500 K and a large amount of CO2 was generated at the combustion field. Our results show that the Compton scattered X-ray analysis can be a novel nondestructive measurement for temperature and chemical states in a combustion reaction.

Laser-Induced Breakdown Spectroscopy (LIBS) For The Characterization Of Methane-Air Laminar Diffusion Flame

Laser-induced breakdown spectroscopy (LIBS) was applied for the characterization of the methane-air laminar diffusion flame, revealing the spatial distribution of its composition. From the measurement, it was found that distribution of the atomic and ionic N emissions produced by the flame had obvious differences, which were mainly distributed in the air area and flame area, respectively. A comparison of the LIBS spectra of air, methane gas, and methane-air laminar diffusion flame showed that the atomic N emissions were mainly produced by the excitation of N2, and the ionic N emissions were more related to the N-containing combustion products. In addition, the correlation between typical emissions and the flame temperature measured by thermocouple was estimated to show that the tendency of the changes in temperature can be characterized by C2 emission intensities. This work provides a new method for real-time online flame temperature measurement, and also provides a reference for revealing the formation process and conversion pathway of each component in the flame.