Analysis of variables in finite element analysis for multi-pass welding in nuclear power plant components, part 1: Comprehensive study with experimental validation using scientific weld specimen

Abstract

The influence of various parameters in welding simulations using finite element analysis (FEA) was investigated in this study. Welding experiments and finite element simulations were conducted to analyze residual stress and post-welding distortion. It was a specially designed V-groove specimen, filled with bead passes using Gas Tungsten Arc Welding (GTAW), that facilitated the measurement of distorted shapes and residual stress. Advanced measurement techniques, including three-dimensional laser scanning and the contour method, were used to capture detailed data on the welded specimen. Three different heat source models (body heat flux, temperature boundary, and Goldak's double-ellipsoidal model) were employed in the simulations, and their effect on residual stress distributions was analyzed. Additionally, the effects of hardening models, bead deposition methods, bead shape modeling, welding sequences, and lumping of weld passes on simulation were systematically analyzed. The findings suggest that a combined approach using different modeling techniques and careful calibration of parameters can enhance the reliability of simulations in predicting weld residual stress and distortions.