开发了一套分析浮式液化天然气(FLNG)系统中船体运动与液舱晃荡耦合响应的数值模拟程序.该程序基于频域势流理论获得船体的频域水动力系数，并根据脉冲响应理论(IRF)实现船体运动的时域计算；基于势流理论采用边界元法进行液舱晃荡的时域预报；通过迭代计算实现运动与晃荡响应的耦合预报.开展模型试验研究固体、液体装载船体在波浪中的运动响应.结合数值计算结果和试验结果研究晃荡和船体运动的耦合机理，讨论了不同液舱布置形式下的耦合响应变化.结果表明：液舱晃荡会显著改变船体的横荡、横摇运动响应，对垂荡运动影响较小；改变液舱宽度可以减小横摇运动引起的晃荡幅值，而横荡激励的晃荡响应主要与晃荡固有频率有关；液舱垂向位置变化仅改变与横摇模态的耦合响应，与横荡运动的耦合作用不变.
This study develops a program to investigate the coupling effects between liquid sloshing and vessel’s motion in the floating liquefied natural gas (FLNG) system. In the program, hydrodynamic coefficients of vessel in frequency-domain are solved and solution of vessel’s motion in time-domain is calculated based on impulsive response function (IRF), liquid sloshing model is built based on potential flow theory and is solved by boundary element method. The solution of vessel’s motion and liquid sloshing are coupled in time domain through iteration method. Model tests of solid and liquid vessels in waves are conducted to validate the feasibility of the program. The coupling mechanism of liquid loading vessel is studied based on numerical and experimental results, and effects of liquid tank arrangement on vessel’s responses are discussed. It is found that vessel’s sway and roll motions are significantly affected by liquid sloshing in tank, while heave motion is slightly affected; the change of tank width can reduced the wave elevation caused by roll motion, and sway motion excited sloshing properties is mainly related to the natural sloshing frequency; the vertical position of liquid tank only affects the coupling effects of sloshing with roll motion mode and has no influences on coupling with sway motion mode.
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