获取界面响应不可测数据的频响探针关键技术研究

目的针对传统逆子结构理论在求解过程中界面响应难以实测的问题,提出一种利用频响探针技术来获取该界面响应的关键技术。方法首先基于该频响探针的动力学微分方程,从理论上推导了该频响探针技术的理论公式,然后对建立的二级单点刚性耦合系统进行了有限元数值验证,将利用频响探针技术预测得到的难测原点频响函数与有限元计算值进行比较,并将该预测值代入逆子结构理论公式中,得到了部件频响函数的预测值,将该预测值与有限元计算值进行了对比验证。结果预测值与有限元计算值高度吻合,验证了该理论的准确性。结论该频响探针关键技术在获取界面响应不可测数据方面,有很好的应用价值。

Research on Key Technology for Obtaining Unmeasured Data of the Interface Response

The inverse sub-structuring method by using the easily measured system-level FRFs to predict the substructure-level FRFs and the dynamic stiffness of coupling interface. In most engineering application practices, the system-level FRFs from coupling degree of freedoms may not be measured accurately because of there might be some fragile structure in the coupling interface and the difficulties of vibration excitation and response measurement for the coupled interface between components within the limited accessible space. In this paper, the aim is to develop a new FRF-based indirect inverse sub-structuring method for the analysis of the dynamic characteristics of a three-component coupled mechanical system without measuring system-level FRFs at the coupling degree of freedoms. Using a frequency response probe to predict the unmeasured interface auto FRF, the theoretical derivation of the theoretical formula of the frequency response probes is given firstly, then the technology is verified by a finite element simulation, showing exact agreement. The new method shows its great application prospect for obtaining unmeasured data from the coupling interface.