Spectral analysis of Ar plasma-arc under different experimental parameters

Electron excitated temperature is one of the most important parameters of Ar plasma-arc. Emission spectrum diagnosis technique has been widely used in the research of electron temperature for its easy operation and small disturbance, where the spectral analysis is the focused content. However, there is still no report about spectral analysis of Ar plasma-arc under different experimental parameters. In this paper, we use the fiber spectrograph for collecting the spectral distribution of the Ar plasma-arc. Then we change the experimental parameters, analyze the influences of the electric current and air current on the spectral distribution. The results show that all these experimental parameters have great influence on the characteristics of spectrum such as spectral line intensity, background signal, etc. It is found that electric current below 100 A, air current below 10 A/min are good for spectral analysis, while two different wavelengths of 696.5 nm and 763.5 nm are suitable for temperature field testing and analyzing. This research provides a good foundation for density field, pressure field and velocity field testing and analyzing, it is also beneficial for us to understand the inner mechanism of Ar plasma-arc.