Additive manufacturing constitutes a promising production technology with potential application in a broad range of industrial areas. In this type of manufacturing process, objects are created from powder particles by adding layers of material upon one another through selectively melting particles from the powder bed. However, understanding the mechanical behavior of the powder during manufacturing as a function of material properties and particle shape is an essential pre-requisite for optimizing the production process. We develop a numerical tool for modelling the transport mechanism of powder particles during additive manufacturing based on the Discrete Element Method (DEM). Our numerical tool accounts for the complex geometric shape of the powder particles as well as for the dynamic boundary conditions inherent to the manufacturing process.