scFEMod – The New Preprocessor for Efficient Assembly and Model Validation

Ove Sommer, Thomas Ertl, Norbert Frisch, Dirc Rose This paper presents a new preprocessor for the assembly of independently meshed car body parts. The assembly process gains more and more importance in the preprocessing of crash-worthiness simulations. It is desirable to take simulation results into consideration for construction decisions already in the early phase of the car development process. At this stage, CAD data unfortunately does not contain any information about constraints like spotwelds or adhesive bondings between substructures. This lack of data has to be resolved by the simulation engineer. We provide an adequate preprocessing tool for this purpose, called scFEMod. scFEMod supports the simulation engineer in effectively defining missing constraints such as point, surface, edge, or line links. All of these can be specified interactively with the mouse pointer. Hierarchical data structures guarantee quick and automatic flange detection so that the assembly process is significantly accelerated. Furthermore, scFEMod can be used to replace separately meshed car body parts by variants which then need to be adapted to the adjacent mesh structure. Subsequently, initial perforations and penetrations can be detected, visualized, and selectively removed. Sensor points can be positioned and oriented in order to compare simulation results with those of physical crash tests. scFEMod allows to distribute non-structural masses over all car body parts they are connected to. Finally, the proper assembly of the whole car body model can be validated.