Self-pulsing of Dielectric Barrier Discharges at Low Driving Frequencies

TL;DR

This study explores the behavior of dielectric barrier discharges at low frequencies, focusing on current dynamics, transition regimes, and effects of dielectric properties, revealing multiple pulsing phenomena and the influence of ferroelectrics.

Contribution

It provides a detailed analysis of current pulsing and transition mechanisms in DBDs at low frequencies, incorporating effects of lossy dielectrics and ferroelectric materials, which were not thoroughly examined before.

Findings

Multiple current pulses per AC cycle explained by electron-ion transport.

Transition from Townsend to CCP discharge depends on pd and frequency.

Ferroelectric materials amplify discharge current.

Abstract

This paper investigates the self-pulsing of Dielectric Barrier Discharges (DBDs) at low driving frequencies. In particular, (a) the dependence of current on the product pd of gas pressure p and the gas gap length d, (b) the effects of lossy dielectrics (in resistive discharges) and large dielectric permittivity (in ferroelectrics) on current dynamics, (c) the transition from Townsend to a dynamic Capacitively Coupled Plasma (CCP) discharge with changing pd values, and (d) the transition from Townsend to a high-frequency CCP regime with increasing the driving frequency. A one-dimensional fluid model of Argon plasma is coupled to an equivalent RC circuit for lossy dielectrics. Our results show multiple current pulses per AC period in Townsend and CCP discharge modes which are explained by uncoupled electron-ion transport in the absence of quasineutrality and surface charge deposition at dielectric interfaces. The number of current pulses decreases with an increasing applied frequency when the Townsend discharge transforms into the CCP discharge. The resistive barrier discharge with lossy dielectrics exhibits Townsend and glow modes for the same pd value (7.6 Torr cm) for higher and lower resistances, respectively. Finally,we show that ferroelectric materials can amplify discharge current in DBDs. Similarities between current pulsing in DBD, Trichel pulses in corona discharges, and subnormal oscillations in DC discharges are discussed. 1