中文摘要：

系泊系统的定位能力是浅水油田作业的软刚臂式单点系泊FPSO安全作业的重要保障,为研究不同水深/吃水比下单点系泊系统的受力性能,针对一艘16万吨级软刚臂单点系泊FPSO,在线性三维势流理论的基础上,基于多体动力学方法,建立FPSO-系泊腿-软刚臂的耦合模型,采用Newman近似法和Pinkster近似法分析了FPSO所受二阶波浪力,在时域内计算了不同水深/吃水比对系泊系统动力响应性能的影响。结果表明,随着水深/吃水比的增加,Newman近似法计算得到二阶波浪力先增大后减小,引起单点系泊系统载荷先增大后减小;而Pinkster近似法计算得到的二阶波浪力逐渐减下,引起单点载荷逐渐减下。在浅水条件下,Pinkster近似法具有较好的适用性,Newman近似法严重低估了FPSO所受的二阶波浪力;在深水条件下,Newman近似法能满足工程计算的要求;适用两种方法的临界水深/吃水比为1.64。

英文摘要：

With the increasing operation life of FPSO and mooring systems,there have been some accidents,which have a great impact on safety in production in oil field. More attentions have been paid to the safety of the Soft Yoke Mooring Systems（ SYMS）. Dynamic response capability of the SYMS under different WD / T（ Ratio of Water depth and FPSO Draft） was analyzed based on multi-body dynamic method. The multi-body coupling model including SYMS and FPSO was established and the hydrodynamic parameter of each body was calculated with linear 3-D potential theory. Second-order wave drift force was calculated by Newman approximation and Pinkster approximation,and the forces on the SYMS under different WD / T were analyzed afterward. A comparison of results using different approximation methods was carried out. With the Newman approximation,the second-order wave force increases first and decrease afterwards with the increase of WD / T,leading to the forces on the SYMS changing synchronously; with the Pinkster approximation,the second-order wave force continually decreases with the increase of WD / T,leading to the forces on the SYMS changing synchronously. It is concluded that Pinkster approximation has a good applicability in shallow water while Newman approximation can meet the requirements of engineering calculations in deep water; and the threshold of WD / T is 1. 64.