Spectroscopic Measurements of Weakly Ionized Argon Plasma Jet

II. Spectroscopic Measurements of Weakly Ionized Argon Plasma Flow Premixed with N₂ in Plenum Chamber

Abstract

The properties of weakly ionized argon plasma flow premixed with N₂ in the plenum chamber are studied by the spectroscopic technique.
A preliminary study is made of the physical processes occuring in the plenum chamber, and it is demonstrated that three competitive reactions of ground state nitrogen molecule, free electron and ground state argon atom for metastable argon atom play an important role in the possible reactions.
The rotational temperatures using the N₂ 2nd positive (0, 0) band are also measured taking account of the overlapping of P and R branches, and it is found that electron temperature is about twice as large as the rotational temperature.
Such a measurement of the free stream in the test section is very difficult because of the lack of the knowledge of the excitation mechanism from X¹Σ state of N₂ to C³II by the metastable Ar atom.