扭力梁横梁结构参数对模态频率的影响分析

Analysis on Effect of Structural Parameters of Torsion Beam Cross Section on Modal Frequencies

作为扭力梁的关键组成部分,横梁对扭力梁模态频率有着重要影响,为从本质上探究横梁结构大变形下对模态频率的作用机理,以在概念设计阶段为扭力梁结构提供设计参考,开展了扭力梁横梁结构参数对模态频率的影响分析.将扭力梁模型抽象为具有定性特点的简化模型,采用Hypermesh建立了相应有限元模型;选取横梁水平位置、开口方向以及开口角度大小等横梁主要参数作为研究对象,采用Hypormorph网格变形以及模型重建的方法改变横梁结构参数,分析了这些参数对扭力梁扭转以及垂直弯曲模态频率的影响规律,得到了以上横梁参数与相关模态频率的特性关系曲线.结果表明:扭力梁模态频率随着横梁开口角度的增大呈线性递减,随着横梁开口方向的改变其各阶模态频率呈正弦变化,以及横梁在远离衬套后会使扭力梁各阶模态频率呈下降趋势.根据扭力梁作用机理分析上述结论,对扭力梁简化模型进行了优化,在不改变横梁质量的情况下,仅优化上述三项横梁结构参数即可较大幅度提高扭力梁模态频率,有效论证了作用机理分析的准确性.

As a key component of a torsion beam,the transverse beam has an important influence on the modal frequency of the torsion beam.In order to explore the mechanism of the modal frequency under large deformation of the beam structure in essence,this study provided the design reference for the torsion beam structure in the conceptual design stage and carried out the analysis on the influence of the parameters of the torsion beam cross beam on the modal frequency.The torsion beam model was abstracted as a simplified model with qualitative characteristics,and the corresponding finite element model was established by Hypermesh.The main parameters of the transverse beam such as beam horizontal position,opening direction and opening angle were selected as the research objects.The parameters of the beam structure were changed by using the Hypormorph mesh deformation and model reconstruction.The influence of the parameters on the torsion and vertical bending modal frequencies of the torsion beam was analyzed,and then the characteristic curves of the above cross beam parameters and the related modal frequencies were obtained.The analysis results indicated that the modal frequencies of the torsion beam decreased linearly with the increase of the opening angle of the beam.With the change of the opening direction of the beam,the modal frequencies of the torsion beam showed different sine.For the beam away from the Bush,the modal frequencies of torsion beams showed a downward trend.According to the analysis of the mechanism,the simplified model of the torsion beam was optimized.The modal frequency of the torsion beam can be greatly improved by optimizing the three beam structure parameters without changing the mass of the beam.The accuracy of the mechanism analysis was proved effectively.