内送粉超声速等离子喷涂流场特性分析  

Numerical Analysis of Plasma Flow with Supersonic Plasma Gun

作　　者：谭超[1] 魏正英[1] 魏培[1] 李本强[1,2] 韩志海[3] 

机构地区：[1]西安交通大学机械制造系统国家重点实验室,陕西西安710049 [2]美国密西根大学机械工程系,密歇根州迪尔伯恩48128 [3]西安交通大学材料学院,陕西西安710049

出　　处：《推进技术》2015年第1期30-36,共7页Journal of Propulsion Technology

基　　金：国防"九七三"资助项目(613112-K3);西安交通大学金属材料强度国家重点实验室开放研究项目(20131310)

摘　　要：应用流体控制方程、传热传质方程、粒子输运方程、Maxwell电磁场方程建立多场耦合数学模型，通过数值计算方法研究超声速等离子喷枪内外等离子体流动特性。所采用的内送粉三维模型包含阴、阳电极固体以及阳极边界层区域，考虑了等离子气体的电离与复合反应，以及局域热平衡效应，得到了超声速等离子喷涂在纯氩和氩氢混合气氛中的气流温度场、速度场分布以及电弧电压分布。结果表明：在加入氢之后，喷枪内等离子体温度提高了30%，速度提高了67%；喷枪外气流速度和温度在距喷嘴出口0~50mm间梯度变化大于喷涂距离50~100mm，且径向速度和温度梯度变化随着喷涂距离增大越来越小。计算得到的电弧电压与测量值相差4.4%，说明了考虑阳极边界层后计算模型的合理性。A multi-physic fields coupling mathematical model was established using fluid controlling equa-tions,heat and mass transfer equations,species transport equations and Maxwell＇s electromagnetic equations, to predict flow field characteristics inside and outside supersonic plasma gun. The three-dimensional model con-tained cathode,anode and anode boundary layers,and took ionization and recombination reactions,as well as non-local thermal equilibrium into consideration. The contours of temperature and velocity of plasma jet were dis-played under argon and argon-hydrogen working conditions, and arc voltage was also described. The results show that gas temperature inside plasma gun increases by 30%, and velocity increases by 67%after hydrogen was added to working gas. Besides,gas temperature and velocity decrease more sharply at distance of 0~50mm from nozzle exit than that of 50~100mm,while the decrease rate of the velocity and temperature are reduced with increasing axial distance. The relative error of calculated arc voltage is 4.4%,compared with measured value,il-lustrating the reasonableness of model after considering anode boundary layer.

关 键 词：数值模拟 超声速喷枪 流场特性 

分 类 号：O359[理学—流体力学] TG174.44[理学—力学]