Simulation of the Marangoni Effect and Phase Change Using the Particle Finite Element Method

A simulation method is developed herein based on the particle finite element method (PFEM) to simulate processes with surface tension and phase change. These effects are important in the sim-ulation of industrial applications, such as welding and additive manufacturing, where concen-trated heat sources melt a portion of the material in a localized fashion. The aim of the study is to use this method to simulate such processes at the meso-scale and thereby gain a better under-standing of the physics involved. The advantage of PFEM lies in its Lagrangian description, al-lowing for automatic tracking of interfaces and free boundaries, as well as its robustness and flex-ibility in dealing with multiphysics problems. A series of test cases is presented to validate the simulation method for these two effects in combination with temperature-driven convective flows in 2D. The PFEM-based method is shown to handle both purely convective flows and those with the Marangoni effect or melting well. Following exhaustive validation using solutions reported in the literature, the obtained results show that an overall satisfactory simulation of the complex physics is achieved. Further steps to improve the results and move towards the simulation of ac-tual welding and additive manufacturing examples are pointed out.