TIG电弧等离子体双温度数值模拟

A two-temperature modeling of TIG arc plasma

基于连续性方程、动量守恒方程、电子能量守恒方程、重粒子能量守恒方程及麦克斯韦方程组,建立了TIG电弧等离子体二维轴对称双温度数学模型.等离子体的热力学性质及输运系数均为电子温度(Te)、重粒子温度(Th)的函数,采用FLUENT软件进行求解得到了TIG电弧等离子体的电子温度场、重粒子温度场、压力场、流场和电势场等,重点比较了等离子体电子温度和重粒子温度的分布规律.结果表明,TIG电弧的外形为典型的钟罩形,在电弧中心重粒子温度与电子温度几乎处处相等,而在电弧边缘及阳极表面两者差异较大,存在很明显的非平衡现象.

A two-dimensional axisymmetric twotemperature mathematical model for TIG arc plasma is established based on the conservation equations of mass,momentum,electron energy and heavy particle energy,as well as Maxwell equations.The thermodynamic and transport parameters of the plasma are taken as a function of electron temperature and heavy particle temperature.The distributions of electron temperature,heavy particle temperature,pressure and velocity for TIG arc are obtained by FLUENT software.The results show that the arc plasma presents a bell shape.Temperatures of electron and heavy particle in the arc plasma show a near-LTE behavior in the core region.While a large deviation from LTE is observed in the near-electrode regions and outside the fringe of arc column,the plasma has a strong non-equilibrium characteristic.