FPSO单点系泊系统动力截断优化设计

浮体系泊系统在海洋工程水池进行模型试验时，由于水池尺度有限，首先对系泊线进行等效截断设计，是被动式混合模型试验的重要一步。截断设计时，基于细长杆理论，模拟系泊线的非线性动力特性，将计算所得时域内的系泊力转换到频域响应，选择有代表性的频率及响应建立目标函数，结合NSGA II优化算法，确定最优截断系泊参数，计算快速准确。针对一作业水深420m的FPSO单点系泊系统，进行水平截断设计。截断前后系泊系统和单根系泊线的静力特性吻合很好。截断系泊系统在不同环境载荷作用下的总体响应和系泊动力，都与截断前一致。证明了截断设计的合理性和准确性，为后续的模型试验工作打下了基础。

Dynamic Truncation Analysis for the Optimization Design of Single Point Mooring System of a FPSO

When model test for mooring system of a floating structure is carried out, considering the dimensional limitation of the offshore basin, equivalent truncation design for the mooring system is an important step for the passive hybrid model test. During the truncation design, based on the slender rod theory, the nonlinear dynamic characteristics is simulated, the mooring forces in time domain are changed into responses in frequency domain, the representative frequencies and points are selected as parameters of objective functions, the NSGA-II optimization method is combined, and then the optimum mooring parameters are determined, which is a quick and accurate method. Horizontal truncation design to an FPSO single point mooring system in 420m water depth is carried out, the static characteristics of the mooring system and single lines all agree very well with each other between truncated and un-truncated system. The global response and mooring tensions of the truncated system under different environmental loads are also consistent with the results of un-truncated system., which verified the reasonability and accuracy of the truncation design, and it is a good base for the future model test in basin.