含环向表面裂纹充液圆柱壳的耦合振动特性分析  

Coupled vibration feature analysis for a fluid-filled cylindrical shell with a circumferential surface crack

作　　者：金超超 朱翔[1,2,3] 李天匀 方敏[1,2,3] JIN Chaochao;ZHU Xiang;LI Tianyun;FANG Min(School of Naval Architecture and Ocean Engineering,Huazhong University of Science and Technology,Wuhan430074,China;Hubei Key Lab of Naval Architecture and Ocean Engineering Hydrodynamics,Wuhan430074,China;Collaborative Innovation Center for Advanced Ship and Deep-sea Exploration,Shanghai200240,China)

机构地区：[1]华中科技大学船舶与海洋工程学院,武汉430074 [2]湖北省船舶与海洋工程水动力学重点实验室,武汉430074 [3]高新船舶与深海开发装备协同创新中心,上海200240

出　　处：《振动与冲击》2018年第23期71-77,共7页Journal of Vibration and Shock

基　　金：国家自然科学基金(51479079)

摘　　要：对含环向表面裂纹有限长充液圆柱壳的耦合振动特性进行了研究。在经典薄壳理论中引入基于断裂力学的线弹簧模型来模拟环向表面裂纹;根据理想流体在柱坐标系下的Helmholtz波动方程,通过添加流体载荷项建立了圆柱壳的耦合振动控制方程,采用波传播法描述耦合系统的振动;经优化迭代法有效地计算对应特定固有频率的轴向波数,在此基础上迭代计算满足特定边界条件和裂纹位置连续性条件的固有频率值。为验证方法的准确性,将计算模型分别退化为真空中完善圆柱壳,真空中裂纹圆柱壳,充液完善圆柱壳,三种情况与文献及有限元方法结果进行对比,验证了方法的准确性;讨论了裂纹深度和裂纹位置参数对圆柱壳固有频率改变的影响。The coupled vibration characteristics of a fluid-filled finite-length cylindrical shell with a circumferential surface crack were studied.Introducing a line spring model to simulate the circumferential surface crack in the classical thin shell theory,according to ideal fluid’s Helmholtz wave equation in cylindrical coordinates,applying the acoustic load of fluid on the shell based on the wave propagation method,and then the fluid-filled cylindrical shell’s coupled vibration control equation was built.The relationship between natural frequencies and axial wave-number of the cylindrical shell was solved with an optimal iterative method.Furthermore,the cylindrical shell’s natural frequencies were iteratively computed to satisfy the specific boundary condition and the continuity condition of crack position.The computation model was degenerated into3cases of a perfect cylindrical shell in vacuum,a cracked one in vacuum and a perfect fluid-filled one.The computation results of3cases were compared with those published in literature and calculated using the FEM,respectively.All results agreed well with each other to verify the correctness of the proposed method.Finally,the effects of crack depth and its position on the cylindrical shell’s natural frequencies were examined.

关 键 词：耦合振动 充液圆柱壳 环向表面裂纹 线弹簧模型 

分 类 号：TH212[机械工程—机械制造及自动化] TH213.3