具有压电元件功能梯度梁的振动控制

考虑一具有压电元件的功能梯度弹性梁. 假设功能梯度材料的物性参数为梁厚度方向坐标的幂函数, 考虑电场作用对结构变形的影响, 应用哈密顿原理, 导出了具有压电元件功能梯度弹性梁的动力学方程, 得到了两端简支功能梯度梁的固有特性与电场强度间的关系. 在此基础上, 通过数值算例讨论了电场强度、 材料的梯度指数等对梁固有特性的影响. 结果表明, 材料梯度化可影响梁的固有频率, 在结构设计中应予以考虑. 通过调整作用在执行元件上的电场强度可以实现对梁振动特性的控制.

Vibration Control of Functionally Gradient Beam Bonded with Piezoelectric Patches

A functionally gradient elastic beam bonded with piezoelectric patches is analyzed in the paper. It is assumed that the physical properties vary as a power function of thickness coordinate variables. The influence of electric field intensity on its structure deformation was considered. Hamilton principle was employed to derivethe equation of the motion of a simply supported functionally gradient elastic beam. The relations between nature characteristics of FGM beam and electric field intensity are presented. The influences ofelectric field intensity and gradient index on the nature characteristics were discussed via numerical examples. It’s found that the vibration characteristics can be controlled effectively by means of regulating the electric field intensity applied on actuators. The effects of the gradient indexes on nature frequency of FGM beam are obvious, so we should pay attention to them in structure designing.