船舶在随机横浪中的奇异倾覆机理

Capsize mechanism of ships in random sea

本文应用非线性随机动力系统理论,从系统稳定性的角度来分析船舶在随机横浪上的运动稳定性,籍此来研究随机海浪中船舶奇异倾覆的机理。本文的研究发现随机动力系统的全局分岔是导致系统失稳并导致船舶倾覆的一种途径。基于这一思路借助随机Melnikov方法,通过求取相流函数零点得到了船舶运动全局稳定性丧失时海浪条件的阈值,从而可以对船舶的抗倾覆能力作出定量的考察。

Basing on the nonlinear dynamics theory, the study of the dynamical stability analysis of ship in random sea was carried out to deduce the capsize mechanism of ship. By virtue of the ideal of ship's undesirable capsize, the result of this paper shows that the globe bifurcation of the nonlinear stochastic dynamic system is one of the way leading to the ship's capsize. Basing on this viewpoint, the stochastic Melnikov method was used to attain the threshold of the dangerous sea condition. And then this threshold can serve as an item to assess the capacity of the ship anti-capsize.