Numerical study of secondary electron emission in a coaxial radio-frequency driven plasma jet at atmospheric pressure

TL;DR

This study uses a numerical model to analyze how secondary electron emission affects the behavior of a coaxial RF-driven plasma jet at atmospheric pressure, highlighting material choices for improved operation.

Contribution

It introduces a 2-D numerical model incorporating secondary electron effects and examines their impact on plasma jet behavior at atmospheric pressure.

Findings

Secondary electron emission significantly influences plasma discharge modes.

Material selection at electrodes and dielectric surfaces can optimize plasma jet performance.

Proper material choices enhance the effectiveness of surface processing applications.

Abstract

In this work we investigate a numerical model of a coaxial RF-driven plasma jet operated at atmospheric pressure. Due to the cylindrical symmetry an adequate 2-D representation of the otherwise 3-dimensional structure is used. A helium-oxygen chemistry reaction scheme is applied. We study the effect of secondary electrons emitted at the inner electrode as well as the inserted dielectric tube and discuss their impact on the discharge behavior. We conclude that a proper choice of materials can improve the desired mode of operation of such plasma jets in terms of materials and surface processing.