基于两种接触模型的柔性体间多次微碰撞问题研究  

Multi-micro impact among flexible bodies using two contact models

作　　者：王检耀 刘铸永[1] 洪嘉振[1] WANG Jianyao;LIU Zhuyong;HONG Jiazhen(Department of Engineering Meehanies,Shanghai Jiao Tong University,Shanghai 200240,Chin)

机构地区：[1]上海交通大学工程力学系,上海200240

出　　处：《振动与冲击》2018年第11期202-206,共5页Journal of Vibration and Shock

基　　金：国家自然科学基金项目(11132007;11772188)

摘　　要：由于柔性体的弹性振动,柔性结构间的一次宏观碰撞过程中,可能发生多次"接触-分离-接触"的微碰撞过程。多次碰撞行为往往会对结构造成各种形式的损害。为了能正确预测任意形状柔性体的多次微碰撞过程,基于三维实体有限元模型,分别采用罚函数法和附加约束法的接触模型,对一柔性杆撞击两端固支梁的问题进行研究,并分析了接触刚度、网格尺寸等参数对两种方法仿真结果的影响。数值结果表明,在罚函数法中,只有通过多次试算得到合适的接触刚度及网格尺寸,才能准确预测出多次微碰撞过程的碰撞次数、碰撞力峰值及碰撞持续时间,而附加约束方法无需选取接触刚度并且对网格尺寸的依赖性较小。In duration of an impact between flexible bodies,multi-micro impact may happen due to structural vibration to lead to ＂contact-separate-contact＂phenomena,and cause various damages of structures. To correctly predict multi-micro impact among flexible bodies,contact bodies were discretized with 3-D solid finite elements and the two contact models named the penalty function method and Lagrange one were used to investigate a case of a flexible rod impacting a beam with two ends fixed. The effects of some parameters,such as,contact stiffness and mesh size on the simulated results of the two methods were analyzed. The numerical results showed that using the penalty method needs several trial calculations to get the appropriate contact stiffness and mesh size,then it can correctly predict impact times,impact force peaks and impact duration in process of multi-micro impact; while using Lagrange method does not need to choose contact stiffness,and it is not so sensitive to mesh size.

关 键 词：柔性体 多次微碰撞 罚函数法 附加约束法 参数影响 

分 类 号：O313.7[理学—一般力学与力学基础]