【摘要】 以直流钨极氮弧焊电弧为研究对象,根据磁流体动力学理论构建轴对称两维数学模型,建立模型时考虑阴极的几何形状,在此模型上对氮气保护TIG焊接电弧进行数值分析.数值模拟所得电弧等离子体温度分布规律显示氮气电弧的最高温区出现于近阳极区域,这个结果与试验情况相当吻合,并与相同条件下氩气电弧的温度场进行了比较.在此基础上对电弧压力和电流密度以及等离子速度场进行了模拟分析;同时分析了不同电流和弧长对等离子流速度分布的影响,结果表明等离子体速度值随着电流的增加而增大,随着弧长的增加而减小.更多还原

【Abstract】 Nitrogen protecting tungsten inert gas(TIG) welding arc was studied.A mathematic model was developed according to the theory of magnetic fluid dynamics.The electrode tip geometry is consi-dered in the model,and the TIG welding arc was numerically analyzed based on this model.The calculated result of arc plasma temperature agrees with the experiment,and is compared with Ar protecting arc at the same condition.The arc pressure,current density distribution and velocity distribution were analyzed based on the model.The influences of the distribution of velocity of the arc plasma about different current and arc length are analyzed.The velocity increases with the increase of current and decreases with the increase of arc length.nitrogen protecting TIG welding;welding arc;magnetic fluid dynamics;numerical analysis更多还原