Prediction of temperature fields based on double-ellipsoidal moving heat source using finite element modelling

The main objective of this study is to generate a better understanding of the use of the finite element (FE) method to predict temperature fields by simulating a gas metal arc (GMA) welding. The welding process on a thick steel plate was selected for study. Heat source factor versus (vs) time tables were created according to the equivalent heat density equations for 3-D moving doubleellipsoidal heat source, and the tables were used in the welding simulation through the heat transfer analysis. The equivalent heat source value of the weld-pool was determined using the method of equal area axis in the heat density distribution, and this heat source value was used in the heat transfer analysis to obtain the temperature fields. The predictions of the temperature fields from the FE models were compared with the measured experimental results. From the comparison, the experimental results closely match those predicted using the FE approach. In future, the temperature fields can then be used as an input file in the thermal analysis to predict the residual stress fields of the welded structure.