A Three Phase Conjugated Heat Transfer Solver Applied To Additive Manufacturing

A. Mark, J. Göhl, S. Ingelsten, T. Johnson, F. Edelvik. 10th International Conference on Multiphase Flow, ICMF, Rio de Janeiro, Brazil, 19-24 May 2019.


Additive manufacturing (AM) is growing rapidly in the industry and is dependent on a number of process parameters and complex multiphysics. In the process, metal powder is melted by a laser beam forming a metal structure. Optimization of the process is very hard and is currently dependent on simple melt pool models. Therefore, there is a lot of trial and error involved in finding a robust AM process. To increase the understanding of the process we propose a physical and CFD-based melt pool model. The model includes a three phase conjugated heat transfer transfer solver, where the gas and melted solid (fluid) are treated with the volume-of-fluid method. To accurately capture the flow of the fluid a temperature dependent rheology model is employed. The phase transition occurs over a small temperature span, in which affected cells are transferred to the other phase solver. Finally, a ray trace based heat source model is used to simulate how an array of powder particles on a substrate are partially melted by a laser beam and the final solidified structure is formed.

Photo credits: Nic McPhee