预紧力对系统频率漂移的影响  

The influence of preload on system frequency variations

作　　者：李太平 翁海宽 江浩 洪岩 齐晓军 LI Taiping;WENG Haikuan;JIANG Hao;HONG Yan;QI Xiaojun(Shanghai Institute of Satellite Equipment,Shanghai 200240, China;Shanghai Yuda Industrial Co., Ltd., Shanghai 200240, China)

机构地区：[1]上海卫星装备研究所 [2]上海裕达实业有限公司,上海200240

出　　处：《航天器环境工程》2017年第6期636-641,共6页Spacecraft Environment Engineering

摘　　要：文章采用Harmonic的谱估计方法,研究了系统不同构件之间通过螺钉连接时,预紧力对系统动态特性的影响。在预紧力相同的情况下,不同量级的外界激励,会造成系统表现出不同的频率响应特性,呈现非线性时不变特性;大量级的外界激励会造成系统预紧力"失效",刚度降低,导致系统的固有频率降低,产生频率漂移,在共振处放大倍数降低。In this paper,the influence of the preload on the dynamic characteristics of a system with screw connections among different components is investigated with the harmonic spectrum estimation method.It is shown that with a preload of the same order of magnitude,the system exhibits different dynamic characteristics or FRFs under excitations of different orders of magnitude,as a non-linear time-invariant system.High level excitation may invalidate the preload,thus lead to reductions of the stiffness,the natural frequency,and the amplification in the resonance region.

关 键 词：预紧力 频率漂移 共振 非线性 Harmonic谱估计方法 仿真分析 试验验证 

分 类 号：V416.2[航空宇航科学与技术—航空宇航推进理论与工程]