Peng Feitan, Chen Luteng, Ye Junyi, Yan Fuwu
SERES Automobile Co., Ltd, Chongqing, 402247, China.
Sci Rep. 2025 Apr 7;15(1):11911. doi: 10.1038/s41598-025-97026-y.
This study examines the problem of inadequate dynamic stiffness at the connection points of car bodies. A method based on modal contribution analysis to assess whether the cause of inadequate dynamic stiffness is a common or unique problem is proposed. Taking the front engine compartment attachment point of a body-in-white as a case study, this research identifies common issues arising from overall modes within the low-frequency range (54/58/74 Hz). To address the problem of frequency mismatch due to different modal truncation frequencies, the left front mounting point of the upper control arm is taken as an example, where the dynamic stiffness at 120 Hz is 8324 N/mm. Through modal contribution analysis, it was identified that the 46 th order engine compartment breathing mode contributed the most, confirming this as a common issue. Common issues can be optimized through frequency avoidance, while unique issues can be optimized using Operational Deflection Shape (ODS) analysis. Early identification of whether an issue is common or unique can significantly enhance the efficiency of NVH (Noise, Vibration, and Harshness) optimization for the vehicle body.
本研究考察了车身连接点处动态刚度不足的问题。提出了一种基于模态贡献分析的方法，以评估动态刚度不足的原因是常见问题还是独特问题。以白车身的前发动机舱连接点为例，本研究识别了低频范围（54/58/74Hz）内整体模态产生的常见问题。为解决由于不同模态截断频率导致的频率不匹配问题，以上控制臂的左前安装点为例，其在120Hz时的动态刚度为8324N/mm。通过模态贡献分析，确定第46阶发动机舱呼吸模态贡献最大，证实这是一个常见问题。常见问题可通过频率回避进行优化，而独特问题可使用运行挠度形状（ODS）分析进行优化。尽早识别问题是常见还是独特，可显著提高车身NVH（噪声、振动与声振粗糙度）优化的效率。
