风浪流作用下半潜平台水动力及其锚泊系统响应分析

针对某半潜平台主体和锚泊系统建立整体水动力模型,基于势流理论,在频域内计算平台在不同浪向下规则波中的水动力及其运动响应;在时域中计算张紧式系泊系统在风、浪、流联合作用下的非线性耦合运动响应,与悬链线系泊系统进行对比分析,结果表明,该半潜平台在高频范围内运动性能良好;深水环境中采用张紧式系泊要比悬链线系泊有优势。     

半潜式生产平台多点系泊选型设计

采用悬链线系泊模式为一座深水半潜式生产平台进行多点系泊选型设计。通过敏感性分析,理顺各类因素对于整体系泊设计方案的影响规律,从而实现参数的合理选取,使得系泊方案的各项技术指标均满足规范要求,最终总结得出一套针对深水浮体多点悬链线系泊系统的设计流程。     

新型干树半潜平台系泊系统的时域耦合分析

我国海洋油气开发正逐步从近海浅水区域不断往远海深水区域发展。随着水深的增加,传统的以锚链为材料,以自重为回复力的悬链线式系泊系统已经不再适用。世界上超深水浮式生产平台基本上都采用张紧式系泊系统,并且中间段采用超轻的聚酯缆材料以降低其施加在平台上的荷载。基于1500米超深水的中国南海环境,开发了一种运动性能良好的新型干树半潜平台。新型平台的系泊系统采用张紧式锚链-聚酯缆-锚链形式。根据平台尺度和环境条件,对系泊系统进行了布置和设计。通过时域耦合方法对系泊系统进行了数值分析,分析结果表明系泊系统强度满足规范和设计要求。     

深水半潜式钻井平台码头抗台风系泊计算分析

深水半潜式钻井平台在码头舾装的周期较长,为确保安全,需对其码头系泊系统进行计算,以得到合理的系泊布置方式。以某深水半潜式钻井平台的码头系泊系统为例,进行风、流载荷共同作用下的抗台风系泊计算分析,建立了多浮体混合带缆系泊系统。     

近岛礁浅水环境下浮式平台系泊系统设计研究

基于有限水深格林函数、Morison公式和时域耦合动力分析方法,以一近岛礁半潜式生产生活平台为研究对象,分析了传统系泊方式(悬链线式和张紧式)和桩柱式系泊方式下平台的运动和系泊系统动力响应。结果表明,通常应用在中深水海域的传统系泊方式,在近岛礁浅水环境下使用时会出现一系列的问题,且进一步优化的空间较小。而文中提出的新型桩柱式系泊系统,很好地解决了传统系泊方式在浅水中存在的问题,且使得船舶的停靠变得更加便利。该文中的分析结果可为平台的水池模型试验和浅水环境下浮式平台系泊系统的进一步设计提供参考。     

深水半潜式平台系泊系统设计研究

随着海洋平台逐步向更深水域的发展,系泊系统设计成了深海平台开发的关键问题之一.该文主要采用时域计算方法对系泊系统进行动力响应分析,给出了深水半潜式平台系泊系统的基本设计方法,并对2 000m水深的半潜式平台系泊缆索进行了8根与12根锚链线的系泊方案的对比分析,结果表明系泊方式不同,锚泊线的张力,系统的运动响应都受到了一定程度的影响.     

半潜式平台两种锚泊系统的静力分析与比较

针对目前半潜式平台常用的全索链和复合索链两种定位系统进行了静力计算和比较,重点推导了复合索链的计算公式,利用该公式可以计算带有任意多重块的复合链的状态参数.文中给出了复合链系泊下的半潜式平台的具体计算步骤,并将结果绘制成了图谱.     

半潜式钻井支持平台在不规则波中的时域耦合分析

基于三维势流理论和莫里森方程,运用水动力软件AQWA,计算半潜式钻井支持平台的水动力特性。同时运用时域耦合方法,计算了风、浪、流共同作用下,半潜式钻井支持平台在三种工况(迎浪、斜浪和横浪)下的运动响应及系泊系统动力响应。时域耦合分析结果验证了该钻井支持平台满足规范要求。     

半潜式平台两种锚泊系统的静力分析与比较

针对目前半潜式平台常用的全索链和复合索链两种定位系统进行了静力计算和比较，重点推导了复合索链的计算公式，利用该公式可以计算带有任意多重块的复合链的状态参数。文中给出了复合链系泊下的半潜式平台的具体计算步骤，并将结果绘制成了图谱。     

非对称半潜起重平台系泊系统设计与分析

半潜式起重平台具有半潜、自航、重型吊栽功能,可适用于不同风浪条件下钻井平台、导管架模块等海上大型结构组块的建造安装和海上废弃平台拆除等吊装运输作业。由于其浮体结构存在不对称性,有必要对其系泊系统开展设计研究。采用AQW A软件对C M H I-1 6 3-1/2非对称半潜起重平台在典型海况下的系泊系统进行分析,仿真计算表明,该平台系泊系统设计方案能够满足西非海域3m高涌浪条件下的系泊要求。     

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。     

FPSO系泊系统参数的动力效应影响分析

利用水动力分析软件AQWA研究了内转塔式单点系泊参数对海上浮式生产储油船FPSO（floating production,storage and affcoading system）系统动力效应的影响特性,定量分析了内转塔位置、系泊缆材料分布、系泊缆预张力、系泊缆数量、系泊缆布置形式等参数对FPSO系统动力效应的影响,对每个系泊参数采取多个特征量进行比较分析,计算结果表明：转塔位置距船艏柱25%Lpp时风标效应及定位效果最好,多成分系泊缆材料分布采取下端钢链9%、聚酯缆90%、上端钢链1%时,系泊缆数量取9根且为3组×3根/组布置时定位效果最好,缆绳受力最小.以FPSO水平偏移量与系泊缆的安全系数为目标,提出了一套系泊系统的优选方案,计算结果表明系泊性能优良,与初步设计方案相比有了显著地提高.文中的计算及分析结果对内转塔式FPSO系泊系统的设计具有一定指导意义.     

基于锚泊系统的半潜式海洋平台定位方法研究

以工作水深1200m、8缆系泊的半潜式海洋平台为对象,研究其系统定位方法,通过改变锚泊系统系泊缆长度来实现平台的定位。建立反映半潜式海洋平台锚泊系统动力响应的多目标优化模型,通过求解得到船体目标位移与最优系泊缆长度,借助多学科软件iSIGHT,通过开发程序接口,调用水动力分析软件ANSYS/AQWA求解器求解,实现了半潜式平台锚泊系统的结构动力响应优化设计。对半潜式平台进行风、浪、流联合作用下的水动力耦合分析,实时控制系泊缆长度来实现平台的定位并保证平台的稳定性。     

Truss Spar平台在不同系泊线组合下的动态响应分析（英文）

The dynamic responses of any floating platform are dependent on the mass, stiffness and damping characteristics of the body as well as mooring system. Therefore, it is very essential to study the effect of individual contributions to the system that can finally help to economise their cost. This paper focuses on the effect of mooring stiffness on the responses of a truss spar platform, obtained by different grouping of lines. The study is part of our present researches on mooring systems which include the effect of line pretension, diameter and azimuth angles. The platform is modelled as a rigid body with three degrees-of-freedom and its motions are analyzed in time-domain using the implicit Newmark Beta technique. The mooring lines restoring force-excursion relationship is evaluated using a quasi-static approach. It is observed that the mooring system with lines arranged in less number of groups exhibits better performance in terms of the restoring forces as well as mean position of platform. However, the dynamic motions of platform remain unaffected for different line groups.     

Dynamic analysis of a dual-spar floating offshore wind farm with shared moorings in extreme environmental conditions

The concept of a shared mooring system was proposed to reduce mooring and anchoring costs. Shared moorings also add complexity to the floating offshore wind farm system and pose design challenges. To understand the system dynamics, this paper presents a dynamic analysis for a dual-spar floating offshore wind farm with a shared mooring system in extreme environmental conditions. First, a numerical model of the floating offshore wind farm was established in a commercial simulation tool. Then, time-domain simulations were performed for the parked wind farm under extreme wind and wave conditions. A sensitivity study was carried out to investigate the influence of loading directions and shared line mooring properties. To highlight the influence of the shared line, the results were compared to those of a single spar floating wind turbine, and larger platform motions and higher tension loads in single lines are observed for the wind farm with shared moorings. The loading direction affects the platform motions and mooring response of the floating offshore wind farm. Comparing the investigated loading directions to the 0-deg loading direction, the variation of mean mooring tension at the fairlead is up to 84% for single lines and 16% for the shared line. The influence of the shared line properties in the platform motions and the structural responses is limited. These findings improve understanding of the dynamic characteristics of floating offshore wind farms with a shared mooring system.     

深海半潜式生产平台张紧式系泊系统安装方案

深海半潜式生产平台通常采用永久张紧式系泊系统,通过搜集整理行业内深水张紧式系泊安装流程的相关资料,对系泊系统海上安装方案进行归纳和总结,详细阐述吸力锚及系泊缆的安装作业流程,并针对海上意外事件出现而采取的相应措施进行说明,为今后深水张紧式系泊系统的海上安装提供参考。     

锚泊辅助动力定位单缆失效时域模拟（英文）

This paper focuses on the research of a semi-submersible platform equipped with a DP-assisted mooring system. Based on the working principles of the DP-assisted mooring system and the model of the platform motion, a time domain simulation program is applied to analyze the impact, in the case of one line failure, on the platform motion, power consumption of the thrusters and the tension of the mooring lines. The results show that, under the10-year wind dominant, a one line failure will have little impact on the tension of the mooring lines. When the failure line is windward,the power consumption will increase greatly with a weakened position of accuracy. However when the failure line is leeward, the power consumption will be reduced with a partly strengthened position of accuracy.     

Time domain simulation of a one line failure for a DP-assisted mooring system

This paper focuses on the research of a semi-submersible platform equipped with a DP-assisted mooring system. Based on the working principles of the DP-assisted mooring system and the model of the platform motion, a time domain simulation program is applied to analyze the impact, in the case of one line failure, on the platform motion, power consumption of the thrusters and the tension of the mooring lines. The results show that, under the 10-year wind dominant, a one line failure will have little impact on the tension of the mooring lines. When the failure line is windward, the power consumption will increase greatly with a weakened position of accuracy. However when the failure line is leeward, the power consumption will be reduced with a partly strengthened oosition of accuracy.     

深水悬链复合锚泊线疲劳损伤计算

以某座Spar平台的锚泊系统为研究对象,首先利用三维绕射理论计算Spar平台主体波浪力,得到平台的总体运动响应时程。再建立复合锚泊线的二维非线性有限元动力分析模型,基于DelVecchio(1992)提出的经验公式,采用迭代的方法计算复合锚泊线的刚度。锚泊线和海床之间的接触作用基于刚性海床假定,基于Morrison公式计算锚泊线的惯性力和拖曳力荷载,根据计算得到的平台主体运动响应时程作为锚泊线顶端输入条件,在时域范围内进行复合锚泊线的动力分析。计算得到中国南海某海域各短期海况条件下复合锚泊线应力的时间历程曲线,采用雨流法对其计数得到对应于各短期海况条件下的疲劳载荷谱。最后根据Miner线性累积损伤模型,对复合锚泊线在长期海况条件下的疲劳损伤进行比较计算。