基于虚拟质量法的水下浮筒流固耦合动态特性分析

The Dynamic Response Analysis of Fluid-solid coupling Properties for Underwater Buoy Based on Virtual Mass

选择水下系泊系统的浮筒为研究对象,对其进行流固耦合特征值分析的基础上,提出虚拟质量的概念。利用流场中结构振动模态的有限元计算方法,结合流体力学的基本方程组,推导出浮筒在水下的虚拟质量矩阵。利用Msc Nastran软件,实现了考虑水作用的浮筒的固有特性分析,将水下计算结果和空气中计算结果进行对比,发现由于水的作用,浮筒的特征值都有不同程度的减小;为这类结构的设计分析提供了一种新的方法。

The buoy of underwater mooring was selected as study object, the virtual mass concept was posed on analysis of fluid-solid coupling eigenvalue for buoy, the underwater virtual mass matrix for buoy was deduced by the finite computing method of structure vibration modal on flow field and the basic equation of hydrodynamics. The primitive properties analysis was carried out considered the action of water by Msc Nastran software and compared the result in air and underwater. The result can be got that the eigenvalue was decreased for the action of water; and a new method was provided for the similar structures design.