Subsea systems for oil exploitation and renewable offshore energy generally employ cables, hoses, risers, umbilical and power energy cables, mooring lines, among other slender components. From the global modeling perspective, all such “lines” can be well represented by classes of structural models according to phenomena of interest for each analysis—eg.: bending/torsion and/or tension/compression loads. In this context, one is frequently interested in static and dynamic effects. Moreover, geometric nonlinearities, hydrodynamic loads and contact with the seabed can play an important role. The present work proposes a general and robust numerical methodology able to establish and analyze complete offshore systems, composed of numerous lines attached to a floating unit. Catenary, lazy-wave, vertical, or other geometric configurations can be considered for each line. The initial guess for the system configuration is produced by a set of analytical solutions, considering a multi-segment extensible catenary formulation. This is implemented into an in-house numerical finite element framework, which models and solves the statics and dynamics of the system. We employ geometrically exact beam and truss models, handling all external loads of interest and contact interactions with the seabed. Case studies following the proposed methodology are exemplified, discussing details on modeling aspects, such as comparing results with other tools/methodologies.

用于石油开采和可再生海上能源的海底系统通常采用电缆、软管、立管、脐带缆和电力能源电缆、系泊线以及其他细长组件。从全局建模的角度来看，所有这些“线”都可以根据每次分析感兴趣的现象，通过结构模型的类别来很好地表示，例如：弯曲/扭转和/或拉伸/压缩载荷。在这种情况下，人们经常对静态和动态效果感兴趣。此外，几何非线性、水动力载荷和与海底的接触也可以发挥重要作用。目前的工作提出了一种通用且稳健的数值方法，能够建立和分析完整的海上系统，该系统由连接到浮动装置的许多管线组成。每条线都可以考虑悬链线、惰性波、垂直或其他几何配置。考虑到多段可扩展悬链线公式，系统配置的初始猜测是由一组解析解产生的。这被实施到内部数值有限元框架中，该框架对系统的静力学和动力学进行建模和求解。我们采用几何精确的梁和桁架模型，处理所有感兴趣的外部载荷以及与海底的接触相互作用。举例说明了遵循所提出的方法的案例研究，讨论了建模方面的细节，例如与其他工具/方法的结果比较。