Numerical modelling of phase changes in laser materials processing using OpenFOAM

Numerical modelling is an important tool for understanding laser processing. It allows clarification of the involved physics, which is difficult or even impossible to measure and observe during experiments. Modelling of laser material processing represents a significant challenge since the coupled multi-physics involves phase changes, rapid evaporation, high melt velocities, and high thermal gradients. For high-fidelity modelling, the laser beam must be appropriately discretised with the implementation of the ray tracing behaviour of each laser ray. In this work, a high-fidelity solver is developed using a laser beam source discretised as Lagrangian particles and complex phase changes implemented through modification of the N-incompressible multiphaseInterFoam solver. Recoil pressure is implicitly implemented through the evaporation of liquid metal instead of an explicit phenomenological implementation through the momentum equation.