波浪作用下潜标拖缆动力学分析

对三维潜标拖缆在规则波作用下的动力响应进行了研究,首先基于集中质量法给出了缆绳在规则波作用下的控制方程,然后提出了两种不同类型的自由端边界条件:质点型和艇型自由端边界条件,前者把拖体视为作三个自由度线运动的质点,而后者把拖体视为作六自由度运动的艇体,最后用有限差分法进行了数值研究。数值计算结果表明潜标拖缆在规则波的作用下,不仅作近似的简谐振动,还会在横向、垂向产生一个偏移量,该偏移量的大小随浪向角的变化而变化,另外受遭遇频率的影响,振动的幅值也随浪向角的变化而呈现不同的特征。

Dynamic analysis of three-dimensional marine cables in regular waves

In this paper,a numerical approach is presented which is capable of predicting the dynamic behavior of three-dimensional marine cables affected by the motion of the buoy.The approach is based upon the lumped-mass-spring model and the finite difference method.Two different boundary conditions of the free end are advaoced: one just considers the linear motion of the buoy,the other considers both the linear and rotary motion of the buoy.A numerical example is also given to demonstrate the validity of the approach.The simulation result shows that,when affected by regular waves,the cable is forced to fluctuate almost harmonically with a displacement occurring in transverse and vertical directions,which varies with different wave direction angles.It also reveals that,affected by frequency of encounter,the fluctuation amplitude varies with different wave direction angles.