Reduced finite-volume model for the fast numerical calculation of the fluid flow in the melt pool in laser beam welding

Abstract

In this paper we propose a reduced two-dimensional finite-volume model for the fast calculation of the melt flow. This model was used to determine the influence of the welding speed, viscosity in the melt and vapour flow inside of the keyhole on the fluid flow field, the temperature distribution, and the resulting weld-pool geometry for laser beam welding of aluminium. The reduced computational time resulting from this approach allows the fast qualitative investigation of different aspects of the melt flow over a wide range of parameters. It was found that the effect of viscosity within the melt is more pronounced for lower welding speeds whereas the effect of friction at the keyhole walls is more pronounced for higher welding speeds. The weld-pool geometry mainly depends on the welding speed.