Modeling Methodology of Tearseams for Invisible PSIR Systems 2001-01-0314
Automotive interiors are undergoing rapid transformation with the introduction of invisible PSIR integral systems. This styling trend requires continuous class A surface for the Instrument Panel (IP) and introduces complexities in the design and analysis of PSIR integral systems. The most important criterion for airbag doors is that it must open as intended, at the tearseam, within the deployment temperature range and without fragmentation. Consequently it is imperative that in analytical simulations, the finite element model of the tearseam is accurate. The accuracy of the model is governed by (a) optimal level of refinement, (b) surface geometry representation and (c) material model.
This paper discusses modeling methodology for tearseams with respect to mesh refinement and the effect of geometry. To accurately predict impact performance and failure of the tearseam, the material at the tearseam and the entire IP system has to be characterized and its failure criteria included in the analytical material model. The methodology for creating an accurate analytical material model has been discussed in “Material Characterization for Predicting Impact Performance of Plastic Parts” . Molded-in tearseams are subject to thin-wall molding conditions and this has been explored in “Predicting Material Processing Degradation” .