中心刚体-柔性梁刚柔耦合动力学模型降阶研究

有限单元法被广泛的采用来描述柔性体的弹性变形,然而有限元节点坐标数目庞大,将会给动力学方程求解带来巨大的计算负担.如何降低柔性体的自由度,是当前柔性多体系统动力学研究的一个重要命题.本文以中心刚体-柔性梁系统为例,采用Krylov方法和模态方法进行降价.然后分别采用有限元全模型、Krylov降阶模型和模态降阶模型,对中心刚体-柔性梁进行刚-柔耦合动力学仿真.仿真结果表明,与采用模态降阶方法相比,采用Krylov模型降阶方法只需要较低的自由度,就可以得到与采用有限元方法完全一致的结果.说明Krylov模型降阶方法能够有效的用于柔性多体系统的模型降价研究.

Model reduction of rigid flexible coupling dynamics of hub-beam system

The finite element method is widely used to describe the elastic deformations of flexible bodies, which leads to a large number of elastic coordinates and large computational burden. In order to reduce the degree of freedom of flexible bodies, a modal method and a Krylov method were used to reduce the degree of freedom of the flexible hub beam system. Then the finite element model, and the reduced models based on modal method and Krylov method were used to do simulation respectively. The numerical simulations show that using the Krylov method shows faster convergence than using the modal method. It means that Krylov method is an efficient method to implement model reduction of flexible multibody system.