The mooring and riser system is the most critical part of an ofshore oil terminal.Traditionally,these two parts are designed separately without considering the nonlinear interaction between them.Thus,the present paper...The mooring and riser system is the most critical part of an ofshore oil terminal.Traditionally,these two parts are designed separately without considering the nonlinear interaction between them.Thus,the present paper aims to develop an inte-grated design process for riser systems with a lazy-S confguration and mooring systems in the ofshore catenary anchor leg mooring(CALM)oil terminal.One of the important criteria considered in this integrated design is the ofset diagram and safe operation zone(SAFOP)related to the mooring system and the riser,respectively.These two diagrams are obtained separately by diferent analyses;therefore,codes or standards are available separately for two components.In this methodol-ogy,the diagrams of both risers and mooring lines are incorporated into a single spiral,thus identifying the safe and failure zones of risers and the mooring lines of the oil terminal.This,in turn,leads to substantial benefts in terms of overall system response,cost reduction,and safety to the ofshore oil terminal.To implement this process,three diferent riser lengths with the lazy-S confguration are considered at three diferent sea depths at the terminal installation site.For each condition,the integrated design of the mooring system and riser is executed according to the derived procedure.Then,coupled dynamic models,wherein both buoys and hoses are included,are developed using OrcaFlex.Results show that the criteria of the relevant regulations are not satisfed by reducing the length of the riser relative to the designed size.Further,as water depth increases,this type of riser confguration shows good coupled performance while interacting with the mooring system.In the cross ofset mode,the maximum margin is created between the ofset diagram and the SAFOP diagram,while the most critical dynamic response of the tanker and terminal system occurs in the near and far modes.Therefore,with this method,the best position for the riser direction with the tanker direction is 90°in the best case.展开更多
The quasi-static analysis method introduced by API RP 2P is well known and accepted as a very useful mooring analysis method. In the early design stage, this method is widely used for preliminary analysis and mooring ...The quasi-static analysis method introduced by API RP 2P is well known and accepted as a very useful mooring analysis method. In the early design stage, this method is widely used for preliminary analysis and mooring parameter selection. However, the quasi-static method of API RP 2P is developed for single-floating-body condition, i. e., only one floating body is considered in the computation procedure. Difficulties arise when it is used for the analysis of a CALM system, which is comprised of two floating bodies (tanker and buoy). This paper presents an analysis procedure for a two-floating-body system based on the quasi-static procedure of API RP 2P with some modifications reflecting special characteristics of the CALM system. Finally, the analysis results of a CALM system are given to illustrate the use of this procedure.展开更多
悬链锚腿系泊系统(catenary leg mooring system,CALM)在海洋油气开采工程中得到了广泛的应用.准确地预测CALM系统运动响应有助于开展输油管的疲劳研究,指导系泊系统的设计,从而防止断锚等危险事故的发生,保证装卸作业的顺利进行和人员...悬链锚腿系泊系统(catenary leg mooring system,CALM)在海洋油气开采工程中得到了广泛的应用.准确地预测CALM系统运动响应有助于开展输油管的疲劳研究,指导系泊系统的设计,从而防止断锚等危险事故的发生,保证装卸作业的顺利进行和人员、装备的安全.基于水动力分析软件,建立包括浮筒、穿梭油轮、系泊线及系船缆在内的不同类型结构的运动响应数值模型;考虑结构间的相互影响,对风浪流作用下的CALM系统进行时域耦合分析;研究了CALM系统在自存工况以及作业工况中的响应特性以及对环境因素的敏感性,得到了危险工况的发生条件及其水动力特征.所得结论可为实际工程设计提供参考和建议.展开更多
文摘The mooring and riser system is the most critical part of an ofshore oil terminal.Traditionally,these two parts are designed separately without considering the nonlinear interaction between them.Thus,the present paper aims to develop an inte-grated design process for riser systems with a lazy-S confguration and mooring systems in the ofshore catenary anchor leg mooring(CALM)oil terminal.One of the important criteria considered in this integrated design is the ofset diagram and safe operation zone(SAFOP)related to the mooring system and the riser,respectively.These two diagrams are obtained separately by diferent analyses;therefore,codes or standards are available separately for two components.In this methodol-ogy,the diagrams of both risers and mooring lines are incorporated into a single spiral,thus identifying the safe and failure zones of risers and the mooring lines of the oil terminal.This,in turn,leads to substantial benefts in terms of overall system response,cost reduction,and safety to the ofshore oil terminal.To implement this process,three diferent riser lengths with the lazy-S confguration are considered at three diferent sea depths at the terminal installation site.For each condition,the integrated design of the mooring system and riser is executed according to the derived procedure.Then,coupled dynamic models,wherein both buoys and hoses are included,are developed using OrcaFlex.Results show that the criteria of the relevant regulations are not satisfed by reducing the length of the riser relative to the designed size.Further,as water depth increases,this type of riser confguration shows good coupled performance while interacting with the mooring system.In the cross ofset mode,the maximum margin is created between the ofset diagram and the SAFOP diagram,while the most critical dynamic response of the tanker and terminal system occurs in the near and far modes.Therefore,with this method,the best position for the riser direction with the tanker direction is 90°in the best case.
文摘The quasi-static analysis method introduced by API RP 2P is well known and accepted as a very useful mooring analysis method. In the early design stage, this method is widely used for preliminary analysis and mooring parameter selection. However, the quasi-static method of API RP 2P is developed for single-floating-body condition, i. e., only one floating body is considered in the computation procedure. Difficulties arise when it is used for the analysis of a CALM system, which is comprised of two floating bodies (tanker and buoy). This paper presents an analysis procedure for a two-floating-body system based on the quasi-static procedure of API RP 2P with some modifications reflecting special characteristics of the CALM system. Finally, the analysis results of a CALM system are given to illustrate the use of this procedure.
文摘悬链锚腿系泊系统(catenary leg mooring system,CALM)在海洋油气开采工程中得到了广泛的应用.准确地预测CALM系统运动响应有助于开展输油管的疲劳研究,指导系泊系统的设计,从而防止断锚等危险事故的发生,保证装卸作业的顺利进行和人员、装备的安全.基于水动力分析软件,建立包括浮筒、穿梭油轮、系泊线及系船缆在内的不同类型结构的运动响应数值模型;考虑结构间的相互影响,对风浪流作用下的CALM系统进行时域耦合分析;研究了CALM系统在自存工况以及作业工况中的响应特性以及对环境因素的敏感性,得到了危险工况的发生条件及其水动力特征.所得结论可为实际工程设计提供参考和建议.
