Numerical analysis of chemical reaction processes in different anode attachments of a high-intensity argon arc

The attachment mode of arc on anode is closely related to the non-equilibrium chemical kinetics process of the anode region of arc. In this paper, the detailed chemical reaction mechanisms in the flow-affected region for both diffuse and constricted argon arc attachments are investigated by means of one-dimensional discharge coupled with a single-fluid, two-temperature model. The collisional-radiative model is used to examine the chemical reaction processes occurring in the anode region, including the arc centreline and fringe region. The numerical results are validated by comparison with available experimental data. The obtained radial distributions of electron temperature, electron density, excited states densities, ionization, and recombination processes reveal that different mechanisms dominate the diffuse and constricted arc-anode attachments.