FLNG液舱存储着大量危险液货，需要对其进行合理的疲劳评估。但目前其疲劳计算工况尚未有明确规定，有必要探究相关参数对疲劳损伤的影响并对规范中工况制定给出一些有参考价值的结论或建议。以满载状态下的某型FLNG为例，首先基于正交试验设计法拟定三向加速度系数的载荷组合工况，然后采用有限元软件对各工况下的液舱关键部位进行疲劳累积损伤计算，最后进行极差分析，归纳出三向加速度系数对不同位置处的热点应力范围及累积损伤结果的影响趋势。结果表明，垂向加速度系数及迎浪工况寿命占比的变化对疲劳累积损伤的影响较为显著。研究成果可为今后FLNG液舱疲劳计算工况的制定提供参考。
It is necessary to carry out a reasonable fatigue assessment for FLNG as a large amount of dangerous liquid cargo is stored in its tanks. However, the loading conditions for fatigue analyses have not been clearly defined at present, so it is important to study the influence of relevant parameters on fatigue damages and give some suggestions for the formulation of loading conditions. Taking some FLNG under full loading condition as an example, first of all, based on the orthogonal experiment design method, the combined loading conditions of three acceleration coefficients are given. Then, the cumulative fatigue damages at key positions under different conditions can be calculated with finite element software. Finally, by conducting range analysis, the influence law of the three parameters on the hot spot stress range and fatigue cumulative damage at different positions is obtained. The results indicate that the change of vertical acceleration coefficient and fraction of life time of 0o head wave condition has a significant effect on fatigue cumulative damage. The research results can provide reference for the formulation of fatigue loading conditions of FLNG tank in the future.
2023,45(8): 62-67 收稿日期：2022-06-10
DOI：10.3404/j.issn.1672-7649.2023.08.013
分类号：U662.2
作者简介：周涛(1988-),男,硕士研究生,研究方向为船舶工程结构强度与疲劳
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