2D Simulation of Streamer Interaction with Surface in Narrow Gap by Dielectric Barrier Discharge in Argon at Atmospheric Pressure /

Abstract

In recent years there have been a growing number of studies that are done on low-temperature plasma. The most common method for the generation of plasma is the electrical breakdown of natural gas in the presence of an electric field. Different discharge types are associated with low-temperature plasma types that lead to streamer development. However, this type of plasma is mostly studied under dielectric barrier discharge. Dielectric barrier discharge is a non-equilibrium high-pressure discharge that is useful for generating excited atomic and molecular species. In this study, we investigate the development and interaction of streamers with dielectric surfaces. This streamer interaction is desired to happen within a narrow gas gap of 0.0001mm (0.1mm) that is placed between two dielectric plates. Both dielectric plates are made of material having different relative permittivity. Streamer developed in the gas gap using argon gas at atmospheric pressure in DBD. The simulation model consists of two dielectric plates separated by a small gap, both plates are covered with conducting metal. This model is based on continuity equations in addition to an equation for conserving electron energy, and Poisson's equation with drift-diffusion equations. The Simulation is performed at atmospheric pressure in argon at temperature (T=300k). This investigation was done by varying the voltage at the HV electrode in different cases and by increasing the gap between dielectric plates this gap is known as the gas gap as well. The focus of the study is on the streamer interaction with the cathode surface at the ground electrode during the first gas ionization under the application of sinusoidal voltage. The main investigating parameters of this study include electric field, electron number density, and surface charge density variation at different time steps. The comparison of electric field, electron number density, and excited argon atoms is also done. The analysis of these parameters shows that by increasing the voltage surface charge density at the cathode increased due to free electrons but by increasing both the gap and voltage it shows a negligible increase. Study shows that surface charges at the dielectric surface are important in this investigation.