A transient temperature distribution in the GTA welding process is analized, employing the 3-dim FEM. The domain which moves with the welding heat source is obtained.
Since the moving solution domain is small compared with the real weld structure, the outer heat loss through the boundary is considered as a conduction heat flow through moving solution domain. The temperature distribution of the element newly generated is decided in accordance with the continuous temperature gradient.
To verify the numerical analysis, some experiments were performed. The fusion lines obtained numerically and experimentally are in good agreements. Thus with small solution domain the temperature distribution of the long welds can be effectively simulated.
