In a joint project between the Fraunhofer Institute for Building Physics (IBP) and the Fraunhofer Institute for Industrial Mathematics (ITWM), a computer-based simulation was developed of the orientation of steel fibres on the basis of flow processes when poured into a formwork. The focus was on self-compacting concrete (SCC) with straight steel fibres and a selected formwork geometry. The software developed is able to represent the flow conditions around inserts or recesses realistically and reliably. This formed the basis for a representation of the orientation of steel fibres placed in concrete structures after the filling process.