The role of vibrational temperature variations in a pulsed dielectric barrier discharge plasma device

• Published in: Contributions to plasma physics (1988) Vol. 60; no. 9
• Main Authors: Nascimento, Fellype, Moshkalev, Stanislav, Machida, Munemasa
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY‐VCH Verlag GmbH & Co. KGaA 01-10-2020; Wiley Subscription Services, Inc
• Subjects: Argon; DBD plasma; Dielectric barrier discharge; Flow rates; Flow velocity; Gas flow; Helium; Parameters; Plasma; Plasma jets; plasma spectroscopy; Plasmas; Reactors; rotational temperature; Surface treatment; vibrational temperature
• ISSN: 0863-1042; 1521-3986
• DOI: 10.1002/ctpp.201900046

The use of dielectric barrier discharge (DBD) plasmas has become a practical way to carry out surface treatment where precise control of the plasma parameters, such as rotational and vibrational temperatures (Trot and Tvib), is required. As the Tvib of an atmospheric pressure plasma jet appears to be the most important parameter related to the improvement of surface treatments, in this work, we analysed two methods to increase the values of Tvib in a DBD plasma jet device. One of the methods is to reduce the exit size (ø) of the DBD reactor, which results in an increase in the measured Tvib values, due to an increase in the pressure inside the reactor. The other method is to change the gas flow rate (GFR) used to produce the plasma jets. This leads to a Tvib reduction when the GFR is increased in the case of using helium or nitrogen as the working gas, but the opposite happens (an increase in the Tvib values) when argon is used, with different phenomena causing the variation of Tvib in each situation.