正交加筋板本征动力特性的尺度效应研究  

Size effect on the intrinsic dynamic characteristics of the orthogonally stiffened plate

作　　者：汤冬 马梓铜 罗锋 陈梦柯 TANG Dong;MA Zitong;LUO Feng;CHEN Mengke(College of Harbour,Coastal and Offshore Engineering,Hohai University,Nanjing 210024,China;Institute of Marine and Offshore Engineering,Hohai University,Nantong 226004,China)

机构地区：[1]河海大学港口海岸与近海工程学院,江苏南京210024 [2]河海大学南通河海大学海洋与近海工程研究院,江苏南通226004

出　　处：《中国舰船研究》2023年第1期213-222,共10页Chinese Journal of Ship Research

基　　金：国家自然科学基金青年基金资助项目(52001113);江苏省自然科学基金青年基金资助项目(BK20190485);中央高校基本科研业务费资助项目(B200202059);南通市基础科学研究资助项目(JC2021006)。

摘　　要：[目的]为了探究不同尺度板架结构本征动力特性之间的联系与区别,分析并探讨正交加筋板中梁、板构件及其耦合结构本征动力特性的尺度效应。[方法]以不同尺度的梁、平板和正交加筋板模型为研究对象,采用有限元方法计算不同尺度梁、平板和正交加筋板模型的固有频率和振型,通过对比自由边界和简支边界下单位尺度模型固有频率和振型随尺度变化规律的异同,探讨边界条件对尺度效应的影响;通过对比耦合结构与梁和平板模型固有频率和振型随尺度变化规律的异同,探究梁、板构件动力耦合对正交加筋板本征动力特性尺度效应的影响。[结果]研究表明,自由边界条件下单位尺度内模型固有频率随尺度的变化规律虽然不再遵循“固有频率与尺度的平方成反比”的规律,但大体上与之相近。[结论]梁、板构件动力耦合会导致单位尺度内正交加筋板模型特定阶数固有频率随尺度的变化规律发生由急剧减小到逐渐增大的转变,还会引起特定尺度和特定阶数模态的错位分布和形态畸变。[Objectives]In order to explore the relationship and difference between the intrinsic dynamic characteristics of the orthogonally stiffened plate of different dimensions,the scale effect of the intrinsic dynamic characteristics of the construction members,such as the beam and the plate,as well as the dynamically coupled structure of the two construction members,the orthogonally stiffened plate,was analyzed and discussed.[Methods]Taking the models of the beam,the plate and the orthogonally stiffened plate as research objects,the natural frequencies and mode shapes of the above-mentioned models of different sizes were calculated by the finite element method.The influence of boundary conditions on the scale effect is discussed in terms of the similarities and differences between the natural frequencies of the beam model and the plate model of the unit scale under the free boundary conditions with those of the models under the simply supported boundary conditions.The influence of dynamic coupling between the construction members of the beam and the plate on the size effect of the intrinsic dynamic characteristics of the orthogonally stiffened plate was investigated by discussing the similarities and differences between the natural frequencies and mode shapes of the orthogonally stiffened plate of unit scale with those of the beam model and the plate model of unit scale.[Results]Numerical results show that the variation of the natural frequencies of the model of unit scale against the size of the model under free boundary conditions no longer strictly follows the law that the natural frequencies are inversely proportional to the square of the size,but it is generally similar,or close to,the law.[Conclusions]The dynamic coupling between the construction members of the beam and the plate,results in the transformation of the variation of the natural frequencies against the size of the orthogonally stiffened plate of unit scale from a rapid decrease to a gradual increase.It also leads to dislocation and distortion of the

关 键 词：本征动力特性 正交加筋板 有限元分析 尺度效应 动力耦合 

分 类 号：U661.4[交通运输工程—船舶及航道工程] TV312[交通运输工程—船舶与海洋工程]