Numerical Modeling of Binary-Gas Plasma Jets in Multi-Arc Plasma Spraying and Validation of Temperature Profiles

Abstract While plasma jets in single-arc systems have been extensively researched, cascaded multi-arc configurations for binary-gas mixtures remain comparatively underexplored. In atmospheric plasma spraying (APS), the use of nitrogen or hydrogen as secondary gases is a prevalent practice to tailor jet properties. This study advances the field by analyzing the flow characteristics of binary-gas plasma jets in cascaded multi-arc systems, providing deeper insights into their influence on particle behavior. A numerical model was developed using temperature-dependent thermodynamic and transport properties, integrating upstream flow conditions from prior plasma generator simulations. To verify its predictive capability, the numerical results were compared with experimental data obtained via optical emission spectroscopic computed tomography (OES-CT). The analysis confirms the numerical model’s accuracy for thermal spraying applications. Notably, the significant temperature increase induced by hydrogen addition is clearly captured in both the OES-CT measurements and the simulation results. This research successfully bridges the process chain from plasma generation to final coating for binary-gas plasma environments.