非均匀预紧力作用下螺栓连接框架结构频响函数计算  

Calculation of frequency response function of bolted frame structures under non-uniform preload

作　　者：陈彦成 孙伟[1,2] 刘晓峰 CHEN Yancheng;SUN Wei;LIU Xiaofeng(School of Mechanical Engineering&Automation,Northeastern University,Shenyang 110819,P.R.China;Key Laboratory of Vibration and Control of Aero Propulsion Systems Under the Ministry of Education,Northeastern University,Shenyang 110819,P.R.China)

机构地区：[1]东北大学机械工程与自动化学院,沈阳110819 [2]东北大学航空动力装备振动及控制教育部重点实验室,沈阳110819

出　　处：《重庆大学学报》2024年第7期32-42,共11页Journal of Chongqing University

基　　金：中央高校基本科研业务费专项资金资助项目(N180312012)。

摘　　要：机械装备中的框架结构大多通过螺栓连接在一起,各螺栓之间出现非均匀预紧会对框架结构的振动特性参数(如频响函数)产生明显的影响。基于有限元法提出了一种考虑螺栓非均匀预紧的框架结构频响函数计算方法。按照频响函数的定义,根据模态叠加原理推导出适用于螺栓连接框架结构频响函数的计算公式;从服务于频响函数计算的需求出发,基于ANSYS软件阐述了螺栓非均匀预紧的模拟及提取包含非均匀预紧的框架结构刚度及质量矩阵的方法;给出了基于ANSYS和Matlab两种软件平台对螺栓连接框架结构频响函数进行计算的分析流程;以一个包含4个连接螺栓的框架结构为对象进行了实例研究,用试验证明了所提频响函数计算方法的合理性,在此基础上从试验及仿真两个角度分析了螺栓预紧力对框架结构频响函数的影响。结果表明,随着螺栓预紧力的增加,框架结构固有频率及频响函数峰值均变大。Many frame structures in mechanical equipment are assembled using bolts,and variations in bolt preload can significantly affect the vibration characteristics of these structures,such as the frequency response function(FRF).This paper presents a method for calculating FRF of frame structures considering non-uniform bolt preload,based on the finite element method.A calculation formula suitable for FRF of bolted frame structures is derived based on the definition of FRF and the principle of modal superposition.By using the ANSYS platform,the simulation of bolt non-uniform preload and the extraction method of stiffness and mass matrices for frame structures with non-uniform preload are elaborated,catering to the FRF calculation requirements.The calculation procedure of FRF of bolted frame structure using ANSYS and Matlab is presented.A case study involving a frame structure with four connecting bolts is carried out to validate the proposed FRF calculation method.On this basis,the influence of bolt preload on the FRF of the frame structure is also analyzed through experiments and simulations.Results show that natural frequency and peak values of FRF increase with higher bolt preload.

关 键 词：螺栓连接 框架结构 非均匀预紧 频响函数计算 有限元建模 

分 类 号：TH131.3[机械工程—机械制造及自动化] O327[理学—一般力学与力学基础]