组合板结构面内和面外振动动刚度法研究

发布时间：2018-07-03 10:00

本文选题：组合板结构 + 动刚度法　；参考：《中国舰船研究院》2016年硕士论文

【摘要】：船舶结构的振动特性分析是研究船舶结构振动的主要内容。过大的振动响应会影响船上人员的工作、休息等,还会引起局部结构的声振疲劳破坏,装有设备的结构在振动时会把振动传给设备,影响电子仪器的正常发挥,这一问题随着船舶及动力装置向高速化大型化发展变得越来越严重。平板是组成船舶结构最基本也是最重要的单元,为了适应工程上的需要,板与板之间常常通过耦合形成复杂的组合板结构。结构在受到激励时,主要产生平面纵波、平面剪切波以及横向弯曲波三种沿板内传播的波,面内振动波和弯曲波不仅在板内传播,而且在交叉连接处发生反射、折射,使组合板结构的振动性能变得复杂。所以单独考虑面内振动或弯曲振动是远远不够的,必须将它们同时考虑在内。本文首先推导矩形板的动刚度矩阵,通过投影法以及一系列的代数运算给出面内振动和弯曲耦合振动的动刚度矩阵的显式表达式,求解结构的固有频率,并通过实验和数值计算进行验证;然后将离散的板单元耦合形成复杂的组合板结构,通过坐标变换将每个板单元局部坐标系下的动刚度矩阵转换成全局坐标系下的动刚度矩阵,再利用经典的有限元理论组装形成整体组合板结构的动刚度矩阵,求解简谐激励下结构的面内振动和弯曲振动响应,得出结构的位移响应场和内力场,通过L型板的算例进行验证;进一步在动刚度法的基础上计算讨论了结构中传播的功率流;最后对典型的双层底舱段结构进行简化,通过动刚度法计算了结构的振动响应,并对结构参数的影响进行分析,为工程应用提供了理论指导。
[Abstract]:The analysis of the vibration characteristics of ship structure is the main content of studying the vibration of ship structure. Excessive vibration response will affect the work and rest of the crew on board the ship, and will also cause fatigue damage of the local structure. The structure equipped with the equipment will transmit the vibration to the equipment during vibration, which will affect the normal performance of the electronic instrument. This problem becomes more and more serious with the development of ship and power plant to high speed. Plate is the most basic and the most important element of ship structure. In order to meet the needs of engineering, the complex composite plate structure is often formed by coupling between plates and plates. When the structure is excited, there are three kinds of waves propagating along the plate: plane longitudinal wave, plane shear wave and transverse bending wave. The in-plane vibration wave and the bending wave not only propagate in the plate, but also reflect and refraction at the cross junction. The vibration performance of composite plate structure is complicated. Therefore, it is not enough to consider the in-plane vibration or bending vibration alone, and they must be taken into account at the same time. In this paper, the dynamic stiffness matrix of rectangular plate is first derived. The explicit expression of the dynamic stiffness matrix of the internal vibration and the bending coupling vibration is given by the projection method and a series of algebraic operations, and the natural frequency of the structure is solved. Then the discrete plate element is coupled to form a complex composite plate structure, and the dynamic stiffness matrix in the local coordinate system of each plate element is transformed into the dynamic stiffness matrix in the global coordinate system by coordinate transformation. Then the dynamic stiffness matrix of the whole composite plate structure is assembled by using the classical finite element theory, and the in-plane and bending vibration responses of the structure under simple harmonic excitation are solved, and the displacement response field and the internal force field of the structure are obtained. The power flow propagating in the structure is further calculated on the basis of the dynamic stiffness method. Finally, the typical bilayer structure is simplified, and the vibration response of the structure is calculated by the dynamic stiffness method. The influence of structural parameters is analyzed, which provides theoretical guidance for engineering application.
【学位授予单位】：中国舰船研究院
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：U661.44

【参考文献】