Numerical Simulation study of effect of Spray Parameters on Characteristics of Plasma Jet Under Very Low-Pressure Plasma Spray Conditions

The Very Low Pressure Plasma Spraying（VLPPS）technology is emerging as a new process for the deposition of uniform and large area coatings derived from the conventional plasma spraying process. However, the characteristics of plasma jet under very low pressure was still not well understood due to experimental diagnosis difficulty and lack of effective simulation method. In this paper a modified Computational Fluid Dynamics (CFD) model and a Direct simulation of Monte Carlo (DSMC) model are used to analyze plasma jet characteristics under VLPPS conditions. The influence of different parameters (including input power, chamber pressure and gas flow rate etc.) is studied systematically. The distributions of velocity, temperature and pressure fields within the plasma jet significantly change with changing different parameters. Numerical simulation results clearly show that the CFD model is feasible method by comparing simulation results with experimental ones.