柔性多体系统非连续动力学模型降阶与仿真技术研究

项目名称： 柔性多体系统非连续动力学模型降阶与仿真技术研究

项目编号： No.11202126

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 刘铸永

作者单位： 上海交通大学

项目金额： 26万元

中文摘要： 混合坐标法是柔性多体系统动力学最常用的建模方法，将柔性体的运动分解为大范围刚体运动和相对浮动基的弹性变形。复杂柔性体的弹性变形大多采用有限单元法描述，其自由度非常庞大。如何降低系统的自由度，提高动力学仿真的计算效率，是当前柔性多体系统动力学面临的一个巨大挑战。这就需要对柔性多体系统动力学模型降阶进行研究。本项目提出一种柔性多体系统动力学全局仿真的研究策略。首先分析刚柔耦合动力学机理，考虑Krylov子空间方法和Gram控制矩阵方法的优点，分别从时域和频域方面，研究二者混合方法处理柔性多体系统连续动力学模型降阶的精度、效率和有效性；其次提出两种策略研究非连续动力学模型降阶技术，一是将碰撞柔性体分为碰撞区和非碰撞区，采用分区模型降阶方法；二是系统整个非连续过程直接模型降阶技术研究。结合实验，探讨所提方法的有效性，并分析模型降阶对柔性多体系统动力学全局特性的影响。

中文关键词： 柔性多体系统；接触碰撞；模型降阶；浮动坐标系；仿真技术

英文摘要： The hybrid coordinate formulation is the most widely used in the modeling of the flexible multibody system dynamics, in which the motion of the flexible body is decomposed into the large overall motion of rigid body and the elastic deformation relative to the floating frame. The finite element method is commonly used to describe the element deformation of the complex flexible body, and the degree of freedom is very large. How to reduce the degree of freedom of the system, and to improve the computational efficiency of the dynamic simulation is a huge challenge of the current flexible multibody system dynamics. Therefore, the dynamic model reduction of flexible multibody systems is required to be investigated. A research strategy of the global simulation of flexible multibody system dynamics is proposed in this project. Firstly, rigid-flexible coupling dynamic mechanism is analyzed, and the advantages of Krylov subspace methods and Gram control matrix method are taken into account respectively. Then the accuracy, efficiency and validity of the mixture of the two methods are investigated to deal with the dynamic model reduction of flexible multibody systems from time domain and frequency domain. Secondly, the two method are proposed to deal with the model reduction technique of the non-continuous dynamic of flexib

英文关键词： flexible multibody system；contact/impact；model reduction；floating frame；simulation technique