基于系泊静态相似的超大型浮体单模块系泊系统简化

Reduction of line number of the mooring system of a single module of VLFS based on static equivalent principle

由多个模块组成的超大型浮体,其系泊系统中的锚链数量会随着模块数量的增加而显著上升。对这样的多模块超大型浮体进行模型试验时,过多的锚链会增加系泊系统的系统误差,增加系泊系统的预张力调节难度。因此,合理地简化系泊系统,减少锚链数量十分必要。本文提出了一种基于静态等效的系泊系统简化方法,将系泊系统的静态等效转化为多目标优化问题,以初始系泊系统与简化系泊系统的水平静回复力和艏摇恢复力矩等效作为目标函数,利用非支配排序遗传算法(NSGA-Ⅱ)求得最优的简化锚链参数,并对使用简化系泊系统的超大型浮体的运动响应进行模拟。通过对比使用简化前后系泊系统运动响应时历的相关性系数,证明对于本文中所使用的浅水悬链式系泊系统,基于静态等效对其进行数量精减并保证浮体的运动响应变化较小是可行的。同时,浮体本身的特性对锚链系统简化的最终效果存在着一定影响。

For the VLFS consisting of multiple modules,the number of mooring chains in the mooring system increases significantly as the number of modules increases.In the model test of such a multi-module VLFS,the excessive number of mooring chains will increase the systematic error and increase difficulty of pre-tension adjustment.So it is necessary to reduce the number of mooring chains based on the static equivalent.In this paper,the reduction of the number of mooring chains based on the static equivalent is converted into a multi-objective optimization problem and the NSGA-Ⅱis used to search for the optimal chain parameters.It is feasible to reduce the chain number of shallow water catenary type mooring system based on static equivalent by comparing the correlation coefficient of the motion response of the VLFS.And the characteristics of the VLFS itself have some effect on the final result of the simplified mooring system.