主动约束层对梁的频率和损失因子的影响

Influence of Active Constrained Layer Treatments on the Frequencies and Loss Factors of Sandwich Beams

由 Ｈａｍ ｉｌｔｏｎ 原理导出了主动约束层阻尼梁结构的机电控制方程，给出了简支边界条件下，压电层在正逆向压电效应两种情况下，电势沿压电层厚度方向的实际分布，得到了相应的运动控制方程；并计算了两种情况下，结构的自然频率和损失因子。

Piezoelectric materials have two interesting characteristics,direct and inverse piezoelectric effects,which permit them to be used as both sensors and actuators.The direct and inverse piezoelectric effects on the natural frequencies and loss factors should be investigated carefully.In this paper,a complete set of governing equations of motion,charge and boundary conditions for the vibration of sandwich beam with active constrained layer treatments are derived by using the Hamilton principle.The distributions of electric potential across the thickness of piezoelectric layer and relevant governing equations are obtained when the direct and inverse piezoelectric effects are considered.Its the first time to obtain such analytical solution for natural frequencies and loss factors of the simply supported beam with active constrained layer damping treatments.The piezoelectric effects on the frequency and loss factors of the sandwich beams are investigated.The numerical results show that piezoelectric effects increase the frequencies but can not change the loss factors evidently.