Local Finite Element Refinement for Accurate Dynamic Stress via Modal Information Only

作     者：Zhou, Yadong 

作者机构：Nanjing Univ Aeronaut & Astronaut Coll Civil Aviat 29 Jiangjun Ave Nanjing 211100 Peoples R China 

出 版 物：《AIAA JOURNAL》 (美国航空航天学会志)

年 卷 期：2020年第58卷第8期

页      面：3593-3606页

核心收录：

学科分类：08[工学] 0825[工学-航空宇航科学与技术] 

主　　题：Dynamic Displacements Stress Concentration Numerical Simulation Frequency Response Functions Model Order Reduction Computational Structural Dynamics Vibration Fatigue Stiffness Matrices Poisson's Ratio Beam (Structures) 

摘      要：Accurate stress responses are the basics for failure analysis of aerospace structures, but they still can be challenging in numerical simulations for dynamic systems. This work exploits the stress mode shapes (SMSs) in local finite element (FE) refinement for the purpose of accurate dynamic stress estimation. Toward structural FE modeling, identification of critical locations via predominant SMSs is theoretically demonstrated. To pursue more accurate dynamic stress, a strategy for local FE refinement is proposed by using the information from stress modal analysis. The strategy involves a two-step procedure. First, modal participation factors (MPFs) are used to extract the predominant modes. Second, retained SMSs are evaluated for the local remeshing. Numerical simulations of a representative thin plate with geometric details were conducted. The SMSs were investigated in detail. Together with MPFs, SMSs can help to localize the dangerous stresses and then refine the local meshes to accurately calculate stress responses. By taking full advantage of numerically obtained SMSs, local structural FE modeling can be applied in a straightforward way with high efficiency. Results indicate that SMSs can reveal the underlying mechanism that governs the overall dynamic stress response.