These slides were presented at the NAFEMS World Congress 2025, held in Salzburg, Austria from May 19–22, 2025.

Abstract

The accurate and efficient simulation of the various connections inside a vehicle body is crucial for achieving precise results in the FEM analysis, particularly in terms of stiffness, fatigue, strength, and vehicle safety. To ensure accuracy and efficiency, three key factors are essential: 1) accurate input data, 2) suitable connection models for each discipline, and 3) seamless interchangeability between the disciplines. Accurate and comprehensive input data is a necessary prerequisite for any simulation. Therefore, accurately transferring the joining information from Computer-Aided Design (CAD) to Computer-Aided Engineering (CAE) is critical. To this end, Magna Steyr has developed a specialized process and software tools to ensure the data consistency between CAD, CAE, and even production, minimizing the risk of discrepancies. When considering the numerical connection models used in simulations, it is essential to recognize that different disciplines often require different models. For durability analysis, precise stress computation is crucial for predicting fatigue life, as errors in stress calculation are magnified by the inclination of the Basquin-Curve. In crash simulations, accurate prediction of failure behavior in a variety of different load situations is essential for predicting the system's response during a crash event. To facilitate efficient collaboration and maintain consistency, stiffness/durability analysis and crash simulation utilize a common baseline mesh for the vehicle structure and employ mesh-independent connection models on top. This approach not only streamlines the simulation process but also allows for efficient iterations and conflict resolution, ensuring accuracy in predictions. To showcase the accurate and efficient simulation of vehicle body connections, this contribution will demonstrate Magna Steyr's approach to connection treatment in simulation. This demonstration will exemplify the complete process from CAD to CAE to the final validation using a real-life example of a vehicle body. The case study will provide valuable insights into how these processes and tools are applied in practice, offering a comprehensive view of the advantages and improvements achieved in vehicle body simulations.