Flow characteristics of metallic powder grains for additive manufacturing

Directed energy deposition technologies for additive manufacturing such as laser selective melting
(SLM) or electron beam melting (EBM) is a fast growing technique mainly due to its flexibility in product de-
sign. However, the process is a complex interaction of multi-physics on multiple length scales that are still not
entirely understood. A particular challenging task are the flow characteristics of metallic powder ejected as jets
from a nozzle and shielded by an inert turbulent gas flow. Therefore, the objective is to describe numerically
the complex interaction between turbulent flow and powder grains. In order to include both several physical
processes and length scales an Euler-Lagrange technology is applied. Within this framework powder is treated
by the Discrete-Element-Method, while gas flow is described by Euler approaches as found in classical Compu-
tational Fluid Dynamics (CFD). The described method succeeded in delivering more accuracy and consistency
than a standard approach based on the volume averaging technique and therefore, is suited for the solution of
problems within an engineering framework.