薄板在冲击载荷下线弹性理想塑性响应的相似性研究  

Study on the similarity of elasticity and ideal plasticity response of thin plate under impact loading

作　　者：李肖成 徐绯[1] 杨磊峰 王帅 刘小川[2] 惠旭龙 刘继军[2] LI Xiaocheng;XU Fei;YANG Leifeng;WANG Shuai;LIU Xiaochuan;XI Xulong;LIU Jijun(Institute for Computational Mechanics and Its Applications,School of Aeronautics,Northwestern Polytechnical University,Xi’an 710072,Shaanxi,China;Aviation Key Laboratory of Science and Technology on Structures Impact Dynamics,Aircraft Strength Research Institute of China,Xi’an 710065,Shaanxi,China)

机构地区：[1]西北工业大学航空学院计算力学与工程应用研究所,陕西西安710072 [2]中国飞机强度研究所结构冲击动力学航空科技重点实验室,陕西西安710065

出　　处：《爆炸与冲击》2021年第11期67-78,共12页Explosion and Shock Waves

基　　金：国家自然科学基金(11972309);陕西省自然科学基础研究计划(2019JQ-625);高等学校学科创新引智计划(111计划)(BP0719007);。

摘　　要：对于比例模型和原型使用不同弹塑性材料的冲击相似性问题,由于弹性和塑性阶段材料特性的差别及其在不同变形阶段的弹性塑性共存现象,将导致原有的结构冲击相似性理论失效。基于薄板冲击问题的理论模型,采用方程分析方法重新推导了材料线弹性以及理想刚塑性共存时的冲击响应的相似律。提出了一种能够同时考虑弹性变形和塑性变形的结构缩放响应相似性分析的厚度补偿方法,并利用数值分析验证了提出方法的适用性。分析结果表明,使用厚度补偿方法得到的比例模型结构响应能够准确地预测原型结构的冲击响应。For the impact similarity problem of the scaled model and the prototype usually have different materials with elastic and plastic properties,the differences of material properties and the coexistence of elastoplastic in different deformation stages will lead to the failure of the previous impact similarity theory.Based on the theory of the thin plate impact problem,the similarity law of impact response was derived by using the method of equation similarity analysis for the material with the linear elastic and ideal rigid-plastic properties.The basic equations of the thin plate structure,such as the energy conservation equation and the strain-displacement equation,were analyzed using equation similarity analysis methods,and the similarity scaling factor of the ideal elastic-plastic thin plate structure was derived.Based on the equation similarity analysis methods,a thickness compensation method that can simultaneously consider the similarity of elastic deformation and plastic deformation was proposed.For the impact similarity problem of the scaled model and the prototype using different ideal elastoplastic materials,this method can be used to calculate the geometric sizes and load conditions of the scaled model through the material properties when the response of the scaled model is similar to that of the prototype.Two finite element models of circular plate mass impact and circular plate velocity impact were established.The geometric sizes and load conditions of the scaled model were calculated through the thickness compensation method when the prototype uses aluminum alloy and the scaled model uses different materials such as steel,brass,etc.The applicability of the thickness compensation method was verified by the response of prototype and scaled model.The results show that the structural response of the scaled model obtained by the thickness compensation method can accurately predict the impact response of the prototype,even though the scale model and the scale model use different materials.

关 键 词：薄板结构 弹塑性耦合 不同材料 相似性分析 

分 类 号：O344[理学—固体力学] V214.4[理学—力学]