Numerical Comparison Between Characteristics of CO₂ and Ar Plasma Arcs With Anode Evaporation

CO
₂
gas is being considered as one of the potential plasma forming gases in plasma arc material processes due to its thermophysical properties, cost, and easy availability. The understanding of the thermal behavior of CO
₂
plasma arc is essential for an effective utilization of it. However, the studies on CO
₂
arc characteristics are scanty. In this study, a 2-D axisymmetric model is built for the simulation of CO
₂
and Ar arcs with and without evaporation of anode. The thermal characteristics of CO
₂
arc are compared with those of Ar arc at different arc currents and anode materials. CO
₂
arc possesses higher temperature compared to Ar arc and the arc current strongly influences the temperature of CO
₂
arc. The anode flux in CO
₂
arc is higher compared to that of Ar arc and the effects of arc current and nature of the anode material on the same are stronger in CO
₂
arc. The arc heating efficiency in CO
₂
is higher than that in Ar and it reduces with increasing arc current.