Study on the safety assessment of free-fall lifeboat system

自由落体救生艇是一种新开发的适用于大型商船和近海结构物的疏散系统。本文采用一种新的数值模拟方法，用一个简单的理论公式计算船体的冲击力，对船体入水过程中的运动和加速度进行了详细的研究。提出了一种新的发射系统，这是本研究的主要研究成果之一。在对救生艇运动进行研究的基础上，利用计算流体力学（CFD）技术对波浪冲击力的数值模拟方法进行了研究。计算结果与实验结果的对比验证了该方法的有效性。并对现有方法的改进进行了研究。本文还对集装箱船艏照明弹轰击现象进行了基础研究，该现象与自由落体救生艇的入水现象类似。

Free-fall life boat is a newly developed evacuation system suitable for use in large merchant ships and offshore structures. Detailed studies on the boat motion and acceleration on boat hull during its water entry are carried out by using a newly-developed numerical-simulation method in which impact force is evaluated by a simple theoretical formula. A new launching system is then proposed as one of the main research results by this study.In addition to the study on the lifeboat motion, a study on the numerical simulation method of wave impact force is carried out by using a technique of computational fluid dynamics (CFD). Comparisons of the computed results of impact force with the experimental ones confirmed the effectiveness of the proposed technique. The improvements achieved over the existing approaches are also studied.Basic studies on the bow flare slamming of container ships, which is a similar phenomenon to the water entry of free-fall lifeboats, are also conducted in this research.