对中心刚体-功能梯度材料梁系统在平面内作大范围转动的动力学特性进行研究。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,在柔性梁纵向位移中计及由于横向变形而引起的纵向缩短项,即非线性耦合变形量。采用假设模态法描述变形,运用第二类Lagrange方程推导得到系统刚柔耦合动力学方程。在此基础上,考虑两种不同梯度分布规律下的功能梯度梁,通过数值算例讨论功能梯度分布规律、材料梯度指数等对作大范围旋转运动柔性梁的动力学特性的影响。结果表明,功能梯度分布规律、材料梯度指数的取值都会对系统的动力学特性产生较大影响。
The dynamics of a hub-functionally graded material beam system rotating in a plane is investigated. It is assumed that the physical properties of the functionally graded material follow certain kinds of power law gradient distribution and vary in the thickness direction. The second order coupling deformation variable, also known as the longitudinal shortening caused by transversal deformation, is considered. By using the method of assumed modes to describe the deformation of the beam, the rigid-flexible coupling dynamic equations of the system are derived via employing Lagrange's equations of the second kind. Then, by considering two different gradient distribution rules, the impact of material distribution and gradient indices on the dynamic characteristics of the hub-functionally graded material beam system undergoing large overall motions are discussed by using numerical simulations. The results show that different functionally gradient distribution rules and material gradient indices will have a great impact on the dynamics of the system.