Numerical Simulation Of Plasma Spray Jet

Plasma jet research is an important theoretical basis for plasma spray process system, characteristics of high-temperature plasma jet directly impact on the quality of the actual spraying. The study on the characteristics of high-temperature plasma jet will help optimizing the kinds of application parameters, allowing industrial applications to achieve the best results. As the plasma jet produced by plasma spray gun is a very complex process, it takes a lot of complex and difficult experiments. The more flow information gets by a way of numerical simulation to solve the problem in the plasma spray process. It has a certain theoretical significance and practial value for plasma spraying process that simulating the complex field of plasma jet by numerical simulation method.This paper uses the fluent simulation and the self-programming to simulate numerically two kinds plasma jet of low temperature and high temperature. Main research contents include the following:1. The paper describes the basic properties and several feature parameters of plasma which provide theoretical basis for the plasma jet model, including the average distance between particles, landau length, classical condition, thin condition, the existence condition of the plasma, the state equation and the macroscopic equation.2. According to the phenomenon of the plasma spray jet, the three-dimensional plasma jet will be reduced to two-dimensional axisymmetric plasma jet to make five basic assumptions. On this basis, the mathematical equations are established for two-dimensional flow field of plasma jet.3. The paper introduces the characteristics of commercial CFD software FLUENT and the strategies of solving problem. FLUENT is used to simulate for low-temperature plasma jet by changing turbulence models and the boundary conditions of speed on the entrance, and verifies the reasonableness of turbulence models and the boundary conditions.4. According to the basic idea of two-dimensional Conservation Element and Solution Element (CE/SE) method, this paper derives the CE/SE method solving the two Viola equations and the Jacobian matrix, and the method is used to simulate high-temperature plasma jet through the self-programming. Finally, it analyzes the variation of physical quantities.