角接头电弧行为数值分析模型

Numerical analysis model for arc behaviors in fillet welding

综合考虑接头几何特征影响,建立了倾斜电极条件下角接头TIG焊电弧三维非对称数值分析模型.基于所建模型,利用FLUENT软件对不同接头角度下焊接电弧温度场、流场、压力场和电势场进行模拟计算.结果表明,模型能够合理反映TIG焊电弧行为特征.电弧形状呈现扁平非对称钟罩型;接头夹角对电弧横断性形态影响相对较大.随着接头夹角的增加,电极端部附近电弧等离子体峰值温度与峰值流速均有所增加,电弧电势峰值也有所提高;同时,电弧挺度增大,但工件表面压力峰值下降明显.

Considering the influence of joint geometrical feature,a three-dimensional asymmetric numerical analysis model for arc is established in TIG fillet welding with inclined electrodes,which is used to calculate the arc temperature field,flow field,pressure field and electric potential field at different joint angles with FLUENT commercial code.The results show that the model can reasonably reflect the characteristics of arc behaviors in TIG fillet welding.The arc has an asymmetrical bell-shape and the joint angle has relatively large influence on cross sectional shape of arc.With the increase of the joint angle,both the peak values of temperature and flow velocity of arc plasma near electrode tip increases to some degree,and the maximum potential of welding arc is also raised.Meanwhile,the arc stiffness is improved,but the pressure peak near the workpiece surface decreases obviously.