波浪中船舶大幅度横摇运动稳性变化的理论计算方法

Theoretics calculation method on ship stability change in big amplitude rolling of ship in waves

在对波浪中船舶横摇稳性特点分析的基础上,提出一种计算船舶大倾角横摇稳性力臂的新方法.在计算每个横剖面左右侧浸深时,考虑船舶在随浪中运动由于首尾不对称造成的纵倾对其浸深及大倾角横摇稳性的影响,根据波浪中重力与浮力平衡、纵倾力矩之和为零这两个条件求取横摇稳性力臂值.为验证本方法,以散货船SWAKOP为例,利用Matlab数学工具语言对其进行计算研究,计算结果显示波浪中船舶大幅度横摇运动对其稳性的变化影响较大,与航海实践相符,同时也表明所提出的这种计算方法是合理和可靠的.

The stability in rolling of ship in waves is introduced and analyzed. The study method of the area of the transverse section is discussed when ship rolls in still water with big angle. While calculating the wetting depth of the left and right side faces of the transverse section, the influence of the trim which acts on the wetting depth of the every transverse section caused by the asymmetry of the fore and stern of ship, and the trim moment which acts on the transverse stability caused by the rolling motion, then in accordance with the condition of the balance of the gravity and buoyancy and the condition that the sum of the trim moment is zero, the value of stability in rolling can be calculated. Based on such a bulk carrier SWAKOP, calculation researches are carried out by use of Matlab＇ s. It is found that the ship stability in big amplitude rolling has changed a lot, which agrees well with nautical practice. And the analysis for this phenomenon is presented from the angle of the mathematical model. Furthermore, the results also demonstrate that the calculation method herein is reliable for ship stability in big amplitude rolling of ship in waves.