An inverse method for arc-droplet-pool coupled GMAW simulation based on an iterative current distribution model

Gas Metal Arc Welding (GMAW) is a vital technology in modern manufacturing. However, fully coupled arc-droplet-pool welding simulations within three-dimensional domains remain challenging due to limitations in numerical techniques. This study proposes an inversed simulation framework to simplify the electromagnetic calculation of GMAW simulations. First, typical droplet shapes were extracted from a molten droplet-pool coupled simulation and used as input for sequential arc plasma simulations. Second, temperature and current density fields during a droplet-falling cycle were obtained from the arc plasma simulations. Furthermore, a mathematical model was developed to represent the axial distribution of the current density along the wire axis, and a global current density distribution model was established. Subsequently, the interpolation of the current model was integrated into the droplet-pool coupled simulation, enabling the iterative computation of the welding temperature field. Compared with the traditional molten droplet-pool coupled simulation, a nearly fully coupled three-dimensional welding simulation was successfully conducted without any loss of computational speed.