Highly efficient and reliable numerical approach for predicting automotive hood displacement: consideration of composite materials and weatherstrip structures

The automotive hood, a closure system for the engine compartment, must be mounted in a suitable position to avoid irregular gaps and flushes when it is initially assembled. The hood panel is mounted with an elastomer part called weatherstrip that is generally made of ethylene propylene diene monomer foam material to seal and reduce vehicle vibration and whistling noise. Because the elastomer material exhibits non-linear mechanical properties and viscoelasticity, which result in unpredictable reaction forces and compression set, the finite element analysis (FEA) of the automotive hood panel displacement with weatherstrip model shows low precision and long computing time. To resolve this issue, in this study, a cost-effective methodology for FEA is introduced by applying compressive stress of a weatherstrip to the distributed surface load in the finite element model without weatherstrip modeling. In addition, a 2D FEA of the weatherstrip is performed to investigate the effects of structural parameters on the reaction force. This work demonstrates a numerical approach for predicting automotive hood displacement by considering the material properties and the structural design variables of the weatherstrip. Therefore, this approach can be applied to other closer parts where it requires highly efficient yet reliable predictive results for mounting position.