An advanced five-unknown higher-order theory for free vibration of composite and sandwich plates  

作　　者：Zhen WU Rui MA Yongzhi LI Yushan XIAO Jie MEI 

机构地区：[1]School of Aeronautics,Northwestern Polytechnical University,Xi’an 710072,China

出　　处：《Chinese Journal of Aeronautics》2021年第9期104-118,共15页中国航空学报（英文版）

基　　金：supported by SKLLIM1902 and the National Natural Sciences Foundation of China(No.11402152)。

摘　　要：Accurate prediction of dynamic characteristics is quite critical to understand the strength of layered structures.Nevertheless,the existing five-unknown higher-order theories encounter difficulties to forecast accurately the dynamic response of sandwich structures.Therefore,a new five-unknown higher-order theory is developed for free vibration analysis of composite and sandwich plates,which possesses the same degree of freedom as those of other five-unknown higherorder theories.The developed model can meet beforehand interlaminar continuity conditions and the free-surface conditions of transverse shear stresses.To assess capability of the proposed model,analytical solution for such composite structures with simply-supported conditions has been presented by employing Hamilton’s principle,which is utilized for analysis of mechanical behaviors of composite and sandwich plates.Compared with the three-dimensional(3 D)elasticity solutions,3 D finite element results and the results obtained from the chosen five-unknown higher-order models,the proposed model can yield accurately natural frequencies of composite and sandwich plates.Even for the thick plates,the higher-order frequencies calculated from the proposed model are in good agreement with the 3 D finite element results.By studying effect of the thickness/length ratios on natural frequencies,it is found that the proposed model is adaptable to predicting natural frequencies of the sandwich plates with the thickness/length ratios between 1/4 and 1/100.In addition,some factors influencing accuracy of five-unknown higher-order models have been investigated in detail.Finally,by means of numerical analysis and discussion,some conclusions have been drawn as well,which can serve as a reference for other investigators.

关 键 词：Analytical solution Five-unknown Free vibrations Higher-order theory Sandwich plates 

分 类 号：V214.8[航空宇航科学与技术—航空宇航推进理论与工程]