Abstract This study investigates the thermal behavior of a WAAM-deposited single bead through two different numerical modelling strategies: Finite Element Method (FEM) and Finite Difference Method (FDM). There is still a lack of direct comparative studies between different discretization strategies applied under identical experimental conditions. In particular, the trade-off between prediction accuracy and computational efficiency in FEM and FDM thermal models has not been sufficiently quantified for WAAM applications. Both approaches integrate a double double-ellipsoid heat source model to better capture the melt pool geometry, resulting in high agreement with experimental profiles and fusion boundaries. The parameters of the double double-ellipsoid heat source were defined from melt pool boundaries extracted from experimental bead cross-sections using an image-processing procedure. In addition, a comparative analysis of modelling accuracy and computational cost is carried out, showing that while both methods yield reliable predictions and comparable accuracy in the estimation of the melt pool geometry and the heat-affected zone (HAZ), the FDM approach reduces the simulation time by approximately a factor of 30 compared with the FEM model, without compromising prediction quality. These findings highlight the potential of simplified thermal models for industrial implementation, offering a practical balance between precision and efficiency in WAAM process simulation.
Sandua et al. (Sat,) studied this question.