Study on plasma jet emission spectrum diagnosis at different gas flow rates

The non-equilibrium plasma jet at atmospheric pressure produces low-temperature plasma in an open environment, which has broad application prospects. Based on the emission spectrum of the argon plasma jet, this paper studies the variation of irradiance, electron temperature, electron density, and metastable particle number when the gas flow rate and axial distance are used as independent variables, respectively. The results show that with the increase in gas flow rate, the irradiance generally shows an increasing trend. At the same gas flow rate, the irradiance decreases with the increase of axial distance. With the increase of gas flow rate, the electron temperature decreases gradually, and the electron density increases gradually at the same axial distance. At the same gas flow rate, the electron temperature and electron density increase first and then decrease with the increase of axial distance. The number density of metastable particles increases with the increase of gas flow rate, and increases, decreases, and then increases with the increase of axial distance.