Four-electrodes DBD plasma jet device with additional floating electrode

TL;DR

This study introduces a four-electrode DBD plasma jet device with an auxiliary floating electrode, demonstrating how varying the electrode length and gas type optimizes plasma power and temperature for potential applications.

Contribution

The paper presents a novel four-electrode DBD plasma jet device with an auxiliary floating electrode, showing how electrode length and gas type influence plasma parameters.

Findings

Optimal pin length maximizes plasma power and vibrational temperature with helium.

Higher emission intensities of OH and NO observed at optimal pin length.

Helium as carrier gas yields better plasma characteristics.

Abstract

A Dielectric Barrier Discharge (DBD) plasma jet in a four electrodes configuration was investigated in order to improve the discharge parameters, such as, plasma power and rotational and vibrational temperatures of molecular species in the plasma plume. The improvement attempts were made by introducing an auxiliary floating electrode in a form of a metallic pin inside the DBD device. That piece was placed near the bottom of the main device, centered in relation to the four powered electrodes, which were covered with a dielectric material. By using metallic pins with different lengths, it was observed that there were considerable variations of the plasma parameters as a function of the pin length. Two carrier gases were tested: argon and helium. With helium as the working gas, it was found that there is an optimal pin length that maximizes the plasma power and its vibrational temperature. In addition, it was verified that for the pin of optimum length the relative intensity of light emissions from OH and NO species achieved higher values than in other conditions studied.