The Mathematical Model Research on MIG Groove Welding Process

Through analysis the MIG groove welding process and the welding experimental result, a complete two-dimensional mathematical model of weld section molten pool characteristics was established. Use Gaussian heat source distribution to describe the weld heat source, introduced the welding speed to establish transient heat source model on the cross section. By introducing scalar of liquid fraction, mushy region dynamic character which was described using “Darcy” model proposed for porous media, and phase change which was taken into account using source-based method, establish a unified liquid and solid control equation, CFD model was established to simulate transient heat and mass transfer phenomena in welding process. The effect of surface tension was considered in the molten pool free surface stress model. The reliability of the model was verified by experiments. The effect of groove angle, groove depth and the welding speed on the molten pool were discussed in this paper.