The moduli and loss factors of viscoelastic materials are frequency-dependent, which brings difficulty to solve the eigenvalue problems. In this note, an estimation method for resonance frequencies and loss factors of viscoelastic composite structures from reduced order models is presented. The reduced order model could be constructed from calculated or measured forced vibration data, and there is no need to know the specific structural matrices or to solve the eigenvalue problem of the vibration system directly. Thus, the difficulties caused by frequency-dependent behaviors of moduli and loss factors of viscoelastic materials are avoided. Numerical examples are presented to illustrate and validate the method.

粘弹性材料的模量和损耗因子与频率有关，这给解决特征值问题带来了困难。在此说明中，提出了一种基于降阶模型的粘弹性复合结构共振频率和损耗因子的估算方法。降阶模型可以通过计算或测得的强制振动数据来构建，无需知道特定的结构矩阵或直接解决振动系统的特征值问题。因此，避免了由频率依赖的模量行为和粘弹性材料的损耗因子引起的困难。数值算例说明和验证了该方法。