Modelling the Role of the Inner Electrode Radius on the Oxygen Negative Corona Discharge in Coaxial Electrode Geometry

Muayad Abdullah Ahmed

doi:10.24996/ijs.2021.62.12.8

Abstract

The charge species plays a vital role in changing the field in direct current discharge (DC). This article introduces a numerical modeling in one dimension of the inner electrode diameter of oxygen-fed negative corona discharge in coaxial electrodes geometry. The properties of negative corona plasma in a concentric cylindrical electrodes (wire-cylinder) were simulated by COMSOL Multiphysics software. Various diameters of negative corona electrode, namely 0.01, 0.025, 0.05, 0.075, and 0.125 mm, were applied, where the diameter of the outer cylindrical electrode was taken as 15 mm. The model was run at atmospheric pressure and the applied negative voltage was -10 KV. Moreover, oxygen gas was used to fill the inter-electrodes distance. Furthermore, the spatial distribution of electrons, positive ions, and negative ions as a function of the diameter of negative electrode of the negative corona discharge were investigated. The study also tested the effects of the electrode diameter of the negative corona discharge on ozone generation. The observed decrease in ozone density with the increase in negative electrode diameter was reasonable and consistent with other results provided by researchers in this field.

Highlights

Electrical corona discharge is considered as a type of self-sustained discharges that appears around the pin and along metals
Continuous or pulsed electrical discharge is possible at atmospheric pressure, where the shape of the discharge depends on the high voltage source applied [1]
The electric field is found in a concentric wire-cylinder system whose radii are a, which represents the radius of the inner electrode, and b which represents the radius of the outer cylinder, i.e. the outer electrode

Summary

Introduction

Electrical corona discharge is considered as a type of self-sustained discharges that appears around the pin and along metals. At a high voltage polarity, the HV positive terminal goes to the cylinder or the outer large diameter of electrode. In this case, a negative corona discharge is created [8, 9]. The competition between the two types of direct current corona discharges is an important matter It allows to distinguish the properties of corona discharges and demonstrate the similarities and differences between them, by using several geometric shapes of the reactor electrodes [01, 10]. Mustafa et al [13] used an infinite element method by using COMSOl Multiphysics software in concentric cylindrical electrodes They tested the effects of temperature on the current and voltage characteristics of the negative corona discharge in air. The main aim of the present study is to analyze the effects of the presence of DC negative corona discharge on the activity of oxygen gas ( ), which represents an electronegative gas

Objectives

Results

Conclusion