水射流冲击作用下船体板架动响应分析

Dynamic response of plate on a ship under water jet impact

水射流冲击是一个极为复杂的流固耦合问题。目前大多数计算模型都是基于一定的假设,例如流体不可压缩,结构为刚性体等。本文基于三维波动方程,考虑流场可压缩性,计及水弹性的影响,采用双渐进法对流场进行求解,采用Abaqus软件模拟板架结构在水柱冲击下的动响应,实现了流体与板架结构的耦合求解,并分别分析了平板和加筋板在水柱冲击作用下的动响应。数值研究表明,冲击区域的中心处受到较大的瞬态冲击,冲击速度改变了射流冲击载荷的大小,使冲击响应随着冲击速度的增加而增大。而板厚的增加改变了板的刚度,对射流冲击具有良好的抵抗作用。

Water jet impact onto elastic panels is a very complex fluid-structure problem. Recently, most numerical models had been approved based on certain assumptions, such as fluid incompressibility, rigid structure and so on. Based on third dimensional wave equations, the paper solved the fluid zone with doubly asymptotic approximation （DAA） method, fluid compressibility and elasticity of water been taken into consideration. Then the coupling of fluid and structure were simulated combining with finite element software Abaqus,the dynamic response of plates and stiffened plates under different water impact velocities were analyzed. The numerical results show that there is a much larger transient impact on the centre of impact area, which may cause severe damage on structure. The magnitudes of impact loads are proportional to the impact velocities for plates but not suitable for stiffened plates. But the thickness of plates have changed stiffness, which gains abilities in resistance to water jet impact.