用有限元法求解水下拖缆振动特性

Solving for Vibration Behavior of Towed Underwater Cables by FEM

在现代反潜、海洋水文和资源勘测中，拖曳式声呐系统得到了越来越广泛的应用．为了进一步提高拖曳式声呐的工作性能，必须研究水下拖缆的振动特性和控制方法．发展了两种分别适用于忽略和考虑弯曲刚度时拖缆的有限单元，并对单元矩阵进行了推导，编制了相应的有限元计算程序，对不同拖速下拖缆的振动固有频率和模态进行了计算．计算结果表明，本算法考虑了变张力、拖缆弯曲和拖体等对拖缆的影响。

The towed sonar system is used extensively in modern antisubmarine, ocean geologic and resources surveying. In order to improve working performance of the towed sonar, vibration behavior and control methods of the towed underwater cables were studied. Two kinds of finite elements applicable for the towed cables both considering and neglecting the bending stiffness were developed. The elements' matrices were deduced. With the programmed FEM software, the cables' natural frequencies and vibration modes were calculated at different velocities. As the effects of varying tension, cable curving and towed body were taken account of, high accuracy was accomplished by this approach.