基于设计波法的FLNG整船强度评估

摘要

本文采用基于设计波法的直接计算法对270 000m3的浮式液化天然气船FLNG进行整船结构强度评估.根据FLNG具体的结构形式和数值分析的最终目的将该装置的实际结构简化,选用适当类型的单元对该装置的结构进行离散而得到FLNG的整船有限元模型.基于三维势流理论并利用中国南海波浪散布图对FLNG进行水动力分析,得到了FLNG在典型装载工况下的波浪压力分布及设计波参数.通过把FLNG承受的波浪压力、惯性力、静水压力与重力等载荷分布到有限元模型上,得到FLNG在典型装载工况下全船的应力水平、应力分布和变形情况.该数值分析结果可在FLNG的初级设计阶段为船体结构强度分析提供有效分析依据,并为FLNG上部模块的设计开发提供船体变形参考.%The overall strength assessment of a 270 000 m3 FLNG (Floating Liquid Natural Gas) was carried out based on design wave approach.Simplified FLNG's structure based on the ship's structure form and numerical analysis's purpose,building a finite element model of FLNG by choose appropriate unit.Hydrodynamic analysis were calculated based on 3-D potential theory and long term prediction using South China Sea scatter diagram,the design wave parameters and hydrodynamic pressure distribution were determined for typical load condition of FLNG.And then loaded hydrodynamic pressure,inertial force,hydrostatic pressure,gravity on the model,obtained stress level,stress distribution,deformation of the hull structure at last.The results of numerical analysis can providing effective basis for overall strength assessment of FLNG at the stage of primary design,it also can providing reference of hull deformation for topside design.