Finite Element Methods for Arc Discharge Simulation

The numerical simulation of industrial arc discharge processes, such as plasma spraying, cutting, and welding, faces severe challenges that include resolution of multiscale features, multiphysics coupling, and robustness in the presence of large gradients. A review of Finite Element Methods (FEMs), particularly the Variational Multiscale (VMS) method, applied to arc discharge simulation is presented. The plasma is modeled as a compressible electromagnetic fluid in chemical equilibrium and thermodynamic nonequilibrium (NLTE). The effectiveness of the NLTE model and the VMS-FEM is demonstrated with the simulation of canonical and industrially relevant arc discharges, namely the plasma flow in transferred and non-transferred arc plasma torches and the free-burning arc.