摘要
该文采用固定界面模态综合子结构法对柔性体的撞击问题进行研究。运用该法研究了刚性块纵向撞击柔性杆的瞬态响应,讨论了柔性体的离散方法对于数值分析计算结果的影响,得到了柔性体合理离散的一些规律。对比分析发现,柔性体的离散并不遵循子结构数目和节点数目越多越好的原则,由于选择的模态数有限,根据所选模态数和结构尺寸,存在一个合理的子结构离散和节点离散数目的范围,在此范围数目内离散结构模型,可以得到合理的计算结果,否则会出更多的伪振荡。通过对撞击系统瞬态动力响应的研究结果表明,子结构法不但可以精确高效地计算撞击过程柔性体瞬态撞击力,而且可以刻画撞击导致的瞬态波在柔性体内的传播机理,从而为复杂柔性系统撞击过程的精细化研究提供了一种简单有效的方法。
The synthetic substructure technique of the fixed-interface mode is adopted to solve the impact problem of a flexible body. The transient wave response of flexible bar struck longitudinally at its free end by a rigid body moving at a finite velocity is investigated by the substructure technique. The influence of the structure discretization on numerical computation results is discussed, and a reasonable method to discretize the flexible bar is obtained. Comparison results show that the flexible discretization doesn＇t accord with the rule that the larger the number of the substructures and the nodes selected in the flexible structure discretization is, the better the results will be. The number of the substructures and the nodes is more reasonable than it is in the special ranges. The ranges are determined by the number of substructure modes and the sizes of the flexible structure. As the number of the substructures and nodes selected in the ranges gives more reasonable and accurate simulations of the impact force response with less pseudo-oscillations. The numerical computation results show that the substructure technique can calculate impact forces precisely and show the propagation mechanism of the transient stress wave and velocity wave along the flexible bar during impact. It provides a simple and effective approach to study the impact process of complicated system precisely.
出处
《南京理工大学学报》
EI
CAS
CSCD
北大核心
2007年第1期51-55,共5页
Journal of Nanjing University of Science and Technology
关键词
柔性机械系统
撞击动力学
子结构法
瞬态波传播
flexible mechanical system
impact dynamics
substructure technique
transient wave propagation
