基于柔性杆理论的脐带缆涡激振动数值模拟系统

Numerical simulation system of vortex-induced vibration of umbilical cables based on flexible rod theory

针对目前海洋脐带缆分析软件缺乏的状况,本文基于MATLAB开发了脐带缆涡激振动数值模拟系统UCVIV-1.0。由于脐带缆的大变形和大转角会产生显著的几何非线性,脐带缆的静态平衡位形和整体力学响应计算采用了细长柔性杆模型,采用尾流振子模型模拟海流作用下的涡激力。该系统界面清晰友好,操作简单,适用于悬链线型脐带缆。选取了一组脐带缆参数,使用该系统进行了静力计算以及涡激振动计算;并将静力结果与采用国外商业软件OrcaFlex计算的结果进行了比对,发现结果吻合程度较高,在一定程度上验证了系统的可行性和准确性。本系统有望为脐带缆设计软件的开发提供借鉴。

Owing to the shortage of marine umbilical cable analysis software,an umbilical cable vortex in⁃duced vibration numerical simulation system(UCVIV-1.0)is developed with MATLAB for static calculation and vortex-induced vibration(VIV)calculation of the umbilical cable.The system interface is clear,friendly,easy to operate,and suitable for catenary umbilical cable.Due to the geometric nonlinearity induced by large deformation and angle of umbilical cable,the slender rod model is applied to calculate the static equilibrium configuration and the overall mechanical response of the umbilical cable.The wake oscillator model is adopt⁃ed to simulate the vortex force under the action of current.The static and VIV responses of umbilical cable are analyzed by using the system.Furthermore,the static calculation results were found to be highly consis⁃tent with those of OrcaFlex upon comparison,verifying the feasibility and accuracy of the system to some ex⁃tent.This system can serve as a reference for the development of umbilical cable design software.