Mathematical simulation of gas shielded twin-tungsten indirect arc

Indirect arc welding is a novelty welding method with advantages of high efficiency, energy saving, low welding stress and deformation. In order to study the arc parameters distribution and the root cause of the low heat input of this novelty welding method, three dimensions finite element model for the indirect arc is established by finite element analysis software. The temperature, velocity and pressure distribution of twin-tungsten indirect arc are obtained. The simulation result is compare with those photos obtained from high-speed camera, and verified the reliability of simulated method. The results show that the twin-tungsten indirect arc deflected to the anode side, the shape of the arc is similarity to inverted bell. The arc parameter of the indirect arc in cathode side is smaller than that of anode side. The parameters of the arc column are much smaller than that of anode surface of TIG welding and plasma arc welding. In the welding process, the work piece doesn't connect electrodes and is mainly heated by the end of the arc column area in where the parameters mentioned above are far smaller than cathode region and anode region is the fundamental reason for low welding heat input and welding penetration.