Study of Cold Ar Atmospheric Pressure Plasma Jet Generated With the Tapered Quartz Tube

In this paper, a cold atmospheric-pressure plasma jet is generated in argon using a single-electrode configuration with the tapered quartz tube. The design of quartz tube is based on the theory of wind tunnel. The lower portion of the tube is divided into two parts: 1) contraction section and 2) test section. Electrical and optical diagnostics are conducted on a plasma jet device, the experimental results show that when the contraction ratio gets higher, the velocity of exit flow is more evenly distributed and the length of atmospheric pressure plasma jet is longer. It shows that a high-concentrated structure is effective to make the argon gas flow more stable and faster.