振动-离心复合下土工离心机的工作模态试验分析  

Operational Modal Test of Geotechnical Centrifuge Combined with Acceleration and Vibration

作　　者：鄂林仲阳 杜强[1,2] 王玉军 罗昭宇[1,2] 魏晓贞 孙爱军[1,2] E Lin-zhong-yang;DU Qiang;WANG Yu-jun;LUO Zhao-yu;WEI Xiao-zhen;SUN Ai-jun(Institute of Systems Engineering, China Academy of Engineering Physics, Mianyang 621999, China;Shock and Vibration of Engineering Materials and Structures Key Laboratory of Sichuan Province, Mianyang 621999, China)

机构地区：[1]中国工程物理研究院总体工程研究所,四川绵阳621999 [2]工程材料与结构冲击振动四川省重点实验室,四川绵阳621999

出　　处：《装备环境工程》2019年第10期105-109,共5页Equipment Environmental Engineering

基　　金：中国工程物理研究院总体工程研究所科技专项(2018KJZ04)

摘　　要：目的获得离心机静止及不同运行状态下的动态特性。方法通过离心机常规模态试验,采用SIMO识别方法,利用力锤产生瞬态激励,计算出激励点与响应点之间的频响函数,通过模态拟合,得到结构的模态参数(频率、阻尼和振型)。进行离心机工作模态试验,测量结构响应并经放大变换,选择2个以上参考点进行互谱分析,获得工作模态参数。结果离心机静止时前两阶模态为绕y轴和绕x轴偏摆,频率分别为3.23、9.94Hz,本身一阶弯曲频率为11.17Hz。不同转动加速度下,离心机一阶工作频率为转动频率;二阶工作模态振型为绕y轴偏摆,频率随着转速的升高而增大。结论通过模态试验分析,获得了该离心机静止及不同运行状态下的模态参数,可为有限元模型修正、结构设计及优化提供参考。Objective To obtain dynamic characteristics of centrifuge in static and different operating states. Methods In modal test with SIMO identification method, force hammer was used to generate transient excitation, calculate the frequency response functions between excitation point and response points, and obtain the modal parameters (frequency, damping and mode of vibration) of the structure by modal fitting. In operational modal test, structure responses were measured and amplified. Two or more reference points were selected for cross-spectral analysis to obtain operational modal parameters. Results When the centrifuge was stationary, the first two modes were deflection around Y axis and X axis;the frequencies were 3.23 Hz and 9.94 Hz respectively;and the first order bending frequency was 11.17 Hz. With different rotational accelerations, the first work- ing frequency was rotational frequency, and the second working mode was deflection around Y axis. The frequency increased with the increase of rotational acceleration. Conclusion Modal parameters under the static and different operating conditions of the centrifuge are obtained through modal test analysis, which can provide reference for modification, structural design and op-timization of finite element model.

关 键 词：模态试验 土工离心机 振动离心复合 

分 类 号：TJ05[兵器科学与技术—兵器发射理论与技术] V416[航空宇航科学与技术—航空宇航推进理论与工程]