缆绳非线性刚度对深海系泊系统的影响

聚酯缆绳因其质轻、无腐蚀而多用于深海系泊系统。聚酯缆绳的材料非线性决定了在实际工程应用中,轴向刚度表现为非线性特性。针对此特性,以动态时域方法分析聚酯缆绳的数值模型,在风、浪、流的环境载荷作用下,考虑FPSO的耦合作用,对比轴向线性刚度与轴向非线性刚度下的船体运动响应和聚酯缆绳的张力。结果表明,非线性刚度更能准确描述船体真实运动及缆绳的张力变化,对以后优化锚泊系统的设计有着重要的意义。

The effect of nonlinear stiffness on the deep mooring system

Due to polyester rope has light weight and non-corrosive characteristics, there is a lot of engineering examples used polyester ropes as mooring lines in deep-water FPSO all over the world. Polyester rope has viscoelastic properties determine the axial stiffness of nonlinear characteristics in the practical engineering applications. The polynomial approximation of nonlinearity method for polyester rope is applied in the dynamic coupled simulation. This paper also researches the dynamics of a turret-moored FPSO with 12 catenary polyester mooring lines are studied to investigate the influence of the hull/mooring coupled system from both linear and nonlinear stiffness of polyester line in the wind, wave and current environment. The results are compared through the dynamic response of FPSO and mooring line tension. These results indicate that the nonlinear elastic method should be used in engineering works to decrease the damaged risk of the structure.