Characteristics of an atmospheric-pressure argon plasma jet excited by a dc voltage

Abstract

A dc-excited plasma jet is developed to generate a diffuse plasma plume in flowing argon. The discharge characteristics of the plasma jet are investigated by optical and electrical methods. The results show that the plasma plume is a pulsed discharge even when a dc voltage is applied. The discharge frequency varies with a change in the applied voltage, the gas flow rate and the gas gap width. It is found that the discharges at different positions of the plasma plume are initiated and quenched almost at the same time with a jitter of about 10 ns by the spatially resolved measurement. Optical emission spectroscopy is used to investigate the excited electron temperature of the plasma plume. The results show that the excited electron temperature decreases with increasing applied voltage, gas flow rate or gas gap width. These results are analyzed qualitatively.

Determination of the Electron Temperature of Atmospheric Pressure Argon Plasmas by Absolute Line Intensities and a Collisional Radiative Model

“…In this paper we apply the ALI-CRM method to measure the axial profile of the electron temperature in a DBD jet and to study how T e (z) depends on the plasma settings. The T e values we found for the AZ is significantly higher than that reported in the past for comparable plasmas [12,23] . Control parameters that were found to be important are the O 2 concentration and the distance between the electrodes d el .…”

Electrical and Spectroscopic Diagnostics of Atmospheric Pressure DBD Plasma Jet

“…Energetic electrons, because of gaining kinetic energy from the applied electric field, excite oxygen species to higher energy levels through inelastic collisions during the drifting process of the electrons. When the applied electric field is greater than the critical value of breakdown, electrons move toward the power electrode and hence the electron density increases through electron avalanche process (Li et al 2013). However, the discharge current flows as soon as the conduction channel is formed in the discharge gap and hence the discharge voltage approaches near zero across the electrode gap.…”

“…The drifting velocity of the spatial charges is related to the electric field and hence the spatial charges are accumulated to the power electrode. With increasing electric field, the drifting velocity of the spatial charges is also increased and hence the discharge frequency increases with the increase of applied voltage (Li et al 2013). This phenomenon is counteracting the increased O 2 gas flow rate with discharge frequency.…”

Effect of the angle between the electric field and the gas flow one on the plasma plume dynamics at atmospheric pressure

“…泛研究, 如空心阴极放电 [7,8] 、介质阻挡放电 [9] 、微放 电 [10] 、电晕放电 [3,11] 等. 通常利用曝光时间为纳秒的 ICCD (Intensified Charge-Coupled Device)拍摄放电照 片, 用于研究等离子体羽的时间演化.…”