Metal powders are selectively molten layer by layer during Selective Electron Beam Melting (SEBM) processes. The density of the resulting material, the spatial resolution as well as the surface roughness of the completed components are complex functions of material and processing parameters. The purpose of this work is to achieve a better understanding of the beam based additive manufacturing process with the help of numerical simulations. A two-dimensional lattice Boltzmann model is developed to investigate melting and re-solidifying of a randomly packed powder bed under the...