Abstract
A three-dimensional model is utilized to predict temperature distribution and fluid flow during the process of gas tungsten arc welding (GTAW). In order to evaluate the effect of the heat flux model on the accuracy of predictions, two types of heat sources — with different natures based on Gaussian surface heat flux and volumetric Goldak's double-ellipsoid heat flux distributions — are taken into account. These heat flux schemes are input into a model simulation of GTAW of AA1050. In the next stage, the transient temperature distribution within the metal being welded is predicted for each heat flux model using FLUENT computational fluid dynamics software. The fusion and heat-affected zones are then determined and compared with each other as well as with experimental observations. The results show that the distribution and intensity of heat flux over the top surface of a workpiece have an important effect on the shape and dimensions of predicted weld pool geometry. Furthermore, the double-ellipsoid heat flux model results produced more realistic data than the Gaussian surface heat flux distribution for the welding conditions considered here.