| Author Name | Affiliation | | Xin Liu | School of Mechanical Engineering, Changshu Institute of Technology, Suzhou 215000, Jiangsu,China | | Mingwei Lu | Department of Virtual Simulation, Suzhou Sonavox Electronics Co.,Ltd., Suzhou 215100, Jiangsu,China | | Yang Zhou | Department of Virtual Simulation, Suzhou Sonavox Electronics Co.,Ltd., Suzhou 215100, Jiangsu,China | | Yuanyuan Zhang | Department of Virtual Simulation, Suzhou Sonavox Electronics Co.,Ltd., Suzhou 215100, Jiangsu,China |
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| Abstract: |
| Nonlinear behavior is important in the vibration test of engineering structures. In this study,a constant response vibration test is proposed for nonlinear element extraction. The method is based on the principle of Harmonic Balance Method (HBM). The stiffness or damping can be regarded as constant for particular steady displacement or velocity response. The displacement or velocity is controlled as a constant in the test. Then the measured Frequency Response Function (FRF) is obtained. The equivalent stiffness or damping is estimated using FRFs for a particular vibration response level. The displacement-dependent stiffness and velocity-dependent damping are fitted to describe the unknown non-linearity. The nonlinear spring and damping force can be obtained by combining the fitting results with HBM using first-order expansion. Constant response vibration test is illustrated through experimental setup to verify its effectiveness. Experimental results show that the procedure is capable of achieving an accurate parameter identification of nonlinear damping and stiffness, which is hopeful for industrial application. |
| Key words: non-linearity identification sinusoidal sweep modal test constant response frequency response function |
| DOI：10.11916/j.issn.1005-9113.23058 |
| Clc Number:O322 |
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| Descriptions in Chinese: |
| 恒响应振动测试应用于非线性单元辨识 刘鑫1， 陆明伟2， 周洋2，张圆媛2， 关集聚1 （1.常熟理工学院 机械工程学院，江苏 苏州215000 2.苏州上声电子股份有限公司，江苏 苏州215100） 摘要：工程结构很少表现出线性特征。工程结构振动测试中非线性十分重要。本研究中，恒响应振动测试应用于非线性单元辨识。基于谐波平衡法原理可知，恒定的稳态位移、速度响应，系统相对于的刚度或阻尼可认定为常数。试验中，通过控制位移、速度保持恒定状态，以获取频率响应函数测试结果。然后，通过恒响应测试得出的频率响应函数估算等效刚度或阻尼，并分别拟合成相应的位移和速度函数以描述系统未知非线性。通过拟合结果与谐波平衡法的结合，可获得非线性刚度和阻尼力。实验结果验证了恒响应振动试验的可行性。实验结果表明，该方法能够实现非线性阻尼和刚度的精确辨识，并具有一定的工业应用前景。 关键词：非线性识别，扫频，模态测试，恒定响应，频率响应函数 |
