接触界面法向刚度等效的新方法  

New Equivalent Method for Normal Stiffness of Contact Interface

作　　者：刘恒[1] 刘意[1] 王为民[2] 

机构地区：[1]西安交通大学机械工程学院,西安710049 [2]东方汽轮机有限公司,德阳618000

出　　处：《机械工程学报》2011年第17期37-43,共7页Journal of Mechanical Engineering

基　　金：国家重点基础研究发展计划(973计划;2007CB707700);国家自然科学基金(51075315);国家科技重大专项(2010ZX04012-014)资助项目

摘　　要：采用典型的粗糙体——刚性面接触模型,针对弹性和弹塑性两种材料,对比分析目前常用的一般接触界面法向刚度等效方法的准确性,说明其在处理弹塑性材料时存在较大误差,而不能完全计入塑性影响是造成此问题的本质原因。通过将整个弹塑性接触系统等效成一个包含全部塑性区域的界面接触层和一个无界面块体,虽然可以计入此种影响,实现和原系统的准确动力等效,但有厚度接触层的引入也将同时带来了单元划分过多、工程实用不便的问题。为此将接触层刚度进一步分离,最终给出一种法向接触刚度等效的新方法。该方法将接触系统等效为无厚度均质弹簧和一个原系统等大小的无界面弹塑性块体,这样不仅能够实现系统动力行为的完全等效,而且可完全计入接触体塑性区域的影响。同时新的等效方法和塑性区域厚度无关,从而避免对原系统网格划分的不便,典型算例的结果说明了新方法的准确性和有效性。Using a rough body-rigid plane contact model,the accuracy of the general normal stiffness equivalent method of contact interface is analyzed under both elastic and elastic-plastic material.The results show that there is a significant error while dealing with elastic-plastic materials,and the essential reason is that the general equivalent method cannot consider the plastic effect of materials completely.By making the elastic-plastic contact system equivalent to an interfacial contact layer and a non-interface block,the original system can be accurately equivalent,because the contact layer includes all the plastic effect.However,introducing the contact layer with a certain thickness can bring the problem of enlarging more elements and inconvenience for practical engineering.In order to overcome the weakness,a new equivalent method of normal contact stiffness is presented by separating the normal stiffness of the contact layer further.Using this method,the contact system is equivalent to non-thickness homogeneous spring and an elastic-plastic block with original size.In this way,the original system can be accurately equivalent,and the plastic effect of the contact body can be taken into account completely.Furthermore,the new equivalent method has nothing with the thickness of plastic zone,so it is convenient for meshing the original system.The results of typical example show the accuracy and effectiveness of the new method.

关 键 词：接触 法向刚度 界面 等效方法 

分 类 号：TH113[机械工程—机械设计及理论] TH117