Abstract: In order to study the attenuation of vehicle instrument panel bolts under vibration, this paper establishes the cylindrical grid through pre-processing software, and the node coordinates are modified to realize the modeling of the thread mesh. Based on the grid, the finite element model of preload attenuation of instrument panel bolt based on LS-DYNA is established, and the accuracy of the finite element model is verified by bench test of preload attenuation of instrument panel bolt. The results show that the acceleration shock vibration will make the bolt preload attenuate significantly. The modified node bolt grid modeling method is suitable for the simulation of bolt preload attenuate. The simulation error of finite element model is within the acceptable range, which has the engineering application value.

Key words: bolted connection; instrument panel; preload force attenuation; finite element analysis; bench test

摘要： 为了对车辆仪表板螺栓在振动作用下的预紧力衰减问题开展研究，文章通过前处理软 件建立圆柱网格，导出后修改节点坐标，实现螺纹网格的建模。基于该网格建立了基于 LS-DYNA 的仪表板螺栓预紧力衰减有限元模型，并根据仪表板螺栓预紧力衰减台架实验验证 了有限元模型的准确性。结果表明，加速度冲击振动会使仪表板螺栓预紧力产生较为显著的 预紧力衰减，修改节点的螺栓网格建模方法适用于螺栓预紧力衰减仿真，有限元模型仿真结 果误差在可接受范围内，具有工程应用价值。

关键词: 螺栓连接；仪表板；预紧力衰减；有限元仿真；台架试验