Theory and Finite-Element Simulation Methodology of Gas Discharge Plasmas

This comprehensive research work explores the intricate realm of gas discharge plasma simulations, offering a profound understanding of its theoretical framework and providing a detailed description of the finite-element simulation process in COMSOL Multiphysics software. Firstly, a solid mathematical foundation essential for modeling gas discharge plasmas is established. Subsequently, a detailed finite-element simulation methodology is presented, along with practical guidance on their implementation within the software and an explanation of their theoretical basis. This includes defining the computational domain, setting appropriate initial and boundary conditions, configuring adaptive meshing, addressing computational challenges, and fine-tuning solver settings. Building upon the provided theoretical framework and simulation methodlogy, a comprehensive case study focusing on negative corona discharges-exemplifying low-temperature plasmas-is presented. First, we provide a comperative parametric study on the influence of various needle electrode geometries and applied voltage magnitudes on the dynamics of negative corona discharges, primarily characterized by Trichel current pulses. Next, the effects of different adaptive meshing strategies, stabilization techniques, time integration methods, and linear system solvers on the convergence, accuracy, and efficiency of the simulations are examined. This paper serves as a valuable resource for students, researchers, engineers, and practitioners engaged in the dynamic field of gas discharge plasma simulations.