Numerical Simulation of a Time-Dependent 3-D GMA Weld Pool Due to a Moving Arc

摘要

A transient three-dimensional GMA weld pool was simulated numerically. The addition of molten material was modeled by an impacting liquid metal spray on the weld pool, with evaporation and latent heat absorption for boiling being computed at the weld pool surface. Realistic arc power and current were applied, i.e., values of more than 10,000 W and 300 A. The mushy zone and the development of reinforcement without specific assumptions were included. The numerical technique consisted of a finite-difference, boundary-fitted coordinate scheme to conveniently compute the nonlinear surface conditions, along with the use of an artificial compressibility method for enforcing incompressibility of the flow field. A numerical solution was presented for a finite workpiece of stainless steel 304. Results included flow and temperature fields, force estimates for various segments of the weld pool and surface geometry. Results were compared with available experimental data.