具有振幅依赖性的纤维增强复合薄板非线性阻尼的时域测试方法

Time domain test method for nonlinear damping of a fiber-reinforced composite thin plate with amplitude dependence

基于Hilbert变换技术,研究具有振幅依赖的纤维增强复合薄板非线性阻尼的时域测试方法。首先,利用Hilbert变换技术,推导获得了具有振幅依赖的复合结构系统非线性阻尼的表达式,明确了从时域测试角度获取非线性阻尼参数的理论原理。然后,编写了MATLAB算法,并用数值算例证明了该算法的正确性。最后,总结并概括出一套合理、规范的测试流程,并对TC500碳纤维/树脂基复合薄板进行了实际测试。实践证明,利用所提出的方法可以有效获得复合薄板在不同衰减时刻对应的阻尼参数,该方法可以用来定量评价不同激励幅度及频率下具有振幅依赖的复合材料结构的非线性阻尼特性。

Based on Hilbert transformation technique,the time domain test method for nonlinear damping of a fiber-reinforced composite thin plate with amplitude dependence was studied.Firstly,by using Hilbert transformation technique,the expression for nonlinear damping of the composite structure system with amplitude dependence was derived,the theoretical principles of acquiring nonlinear damping parameters through time domain measurement were clarified.Then,the algorithm was written with MATLAB and numerical examples were used to prove the correctness of the algorithm.Finally,the reasonable and standard test procedures were summarized and applied in the real measurement of a TC500carbon fiber/resin composite thin plate.It was shown that the proposed method can effectively acquire its damping parameters at different decay instants,so it can be used to quantitatively evaluate nonlinear damping characteristics of composite structures with amplitude dependence under different excitation amplitudes and frequencies.