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.

中文翻译：

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用于预测汽车发动机罩位移的高效可靠的数值方法：考虑复合材料和挡风雨条结构


汽车引擎盖是发动机舱的封闭系统，在最初组装时必须安装在合适的位置，以避免出现不规则的间隙和齐平。引擎盖板安装有称为挡风雨条的弹性体部件，该弹性体部件通常由三元乙丙泡沫材料制成，用于密封并减少车辆振动和啸叫噪音。由于弹性体材料表现出非线性力学性能和粘弹性，从而导致不可预测的反作用力和压缩永久变形，因此采用挡风雨条模型对汽车发动机罩面板位移进行有限元分析（FEA）精度低且计算时间长。为了解决这个问题，在本研究中，引入了一种经济有效的有限元分析方法，通过将挡风雨条的压应力应用于有限元模型中的分布式表面载荷，而无需进行挡风雨条建模。此外，还对挡风雨条进行了二维有限元分析，以研究结构参数对反作用力的影响。这项工作展示了一种通过考虑挡风雨条的材料特性和结构设计变量来预测汽车发动机罩位移的数值方法。因此，这种方法可以应用于其他需要高效且可靠的安装位置预测结果的较近部件。