Effect of Cathode-Plasma Coupling on Plasma Torch Operation Predicted by a 3D Two-Temperature Electric Arc Model

Abstract In a DC plasma spray torch, the plasma-forming gas is most intensively heated and accelerated at cathode arc attachment due to very high electric current density this location. A proper prediction of is, therefore, essential for understanding jet formation operation. However, numerical studies mostly deal with transferred arcs or conventional torches tapered cathodes. study, 3D time-dependent two-temperature model combined sheath applied commercial cascaded-anode torch SinplexPro fitted wide single cathode. The used investigate effect bidirectional cathode-plasma coupling on predicted flow. plasma-cathode interface takes into account non-equilibrium space-charge establish thermal balance interface. radial profiles parameters (voltage drop, electron temperature interface, Schottky reduction in work function) were computed surface tip latter developed open-source CFD software Code_Saturne. It makes it possible calculate flow fields inside outside as well enthalpy electromagnetic phase electrodes. This study shows that inclusion MHD results higher constriction attachment, more plausible distribution, reliable voltage cooling loss, consistent torch.