| This thesis presents the results of numerical simulation of the negative electric corona discharge for the two-dimensional point-plane geometry, comprising of a hyperboloidal needle as the corona electrode and an infinitely large ground plate, perpendicular to the needle. Four different mathematical models of the corona discharge in oxygen and air have been studied: five-species, three-species, two-species, and single-species models. The hybrid numerical algorithms are employed for the numerical studies and they are based on five different numerical techniques: Boundary Element Method, Finite Element Method, Method of Characteristics, Finite Difference Method, and Donor-Cell Method. The hybrid BEM-FEM technique is utilized to calculate the electric field. The last three methods are used to predict the space charge density distribution. Double iterative loops are employed in all algorithms: the electric field and space charge density are solved sequentially until convergence is reached for all involved parameters.;Keywords. negative electric corona discharge, numerical simulation, Boundary Element Method, Finite Element Method, Method of Characteristics, Finite Difference Method, Donor-Cell Method.;The following parameters of the corona discharge are analyzed: the space charge density distribution along the axis of symmetry, lines of equal charge density for the ionic species in the entire air gap, electric field distribution along the axis of symmetry, the total corona current for different voltage waveforms and parameters of the electric circuit, and current density distribution on the ground plate. The concentrations of ozone molecules along the axis of symmetry and in the air gap are also presented in this thesis. The effect of pressure on all parameters is discussed for the two-species model. |
