单点系泊船舶甲板上浪风险分析

Risk analysis for green water of single-point moored ship

[目的]旨在对单点系泊船舶甲板上浪风险进行预报。[方法]提出采用气隙与耦合动态分析相结合的方法,对不同海况下船舶甲板及艏部舷墙的关键观测点的气隙高度进行时域动态分析,以识别艏艉为单点系泊的船舶易发生甲板上浪的位置。同时,运用极值分析理论和蒙特卡罗方法,计算各关键观测点发生的甲板上浪失效概率。[结果]结果显示,各点位中采用极值分析理论和蒙特卡罗方法预报得到的最大甲板上浪失效概率分别为1.46×10;及9.93×10;。[结论]通过对比发现,极值理论的预报结果偏大。若样本空间不大,运用极值理论可以较保守地预测出甲板上浪失效概率。

[Objective]The purpose of this paper is to predict the green water risks of a single-point moored ship.[Methods]Therefore, a combined method of coupled dynamic analysis and air gap analysis is proposed. The air gap analysis points are chosen on the deck and bulwark of the ship,where the air gaps of these points under different sea states are calculated using dynamic analysis in the time domain. It is found that the bow and poop deck are the position where green water occurs most on the single point moored ship. Based on the extreme value theory and Monte Carlo method respectively, the failure probability of green water at several key analysis points are calculated. [Results]Among all points, the maximum probability of green water is1.46×10;based on the extreme value theory, while the result of the Monte Carlo method is 9.93×10;.[Conclusions]In comparison with the failure probability of green water calculated via the Monte Carlo method, the value calculated via the extreme value theory is higher. When the sample space is not large enough, the extreme value theory can conservatively predict the risk of green water.