基于小波变换的非线性阻尼辨识方法研究

根据阻尼、应变、时间三者之间的关系,提出了辨识非线性阻尼的分段线性化小波变换方法。通过对不同特性的阻尼进行仿真和分析,得出了满意的结果,证明了该算法的有效性和准确性。由于在非均匀应力场下得到的阻尼只是一个体积平均值,为了克服这一点,在传统阻尼试验装置的基础上,开发了具有准均匀应力场的梯形等强度梁试件。试验结果表明,所研究的阻尼合金的阻尼能力随着应变的增加而增加,呈现出明显的非线性关系。

Research on the Identification of Nonlinear Damping Based on the Wavelet Analysis

According to the relationship between damping,strain and time,the wavelet transform method with piecewise linearization is put forward to identify the nonlinear damping of alloy material.The satisfactory results are obtained through simulations of damping with different properties.It is demonstrated that the method presented is effective and accurate.The damping measured in a non-uniform stress field is only a volumetric average.To overcome this deficiency,a trapezoid specimen with quasi-uniform stress field is developed on the basis of the traditional damping experimental equipment.It has been concluded from the experimental results that the damping capacity of the alloy Al-33Zn-6Si increases with the increasing strain.The relation between strain and damping appears obviously to be nonlinear.