For the floating structures in deepwater, the coupling effects of the mooring lines and risers on the motion responses of the structures become increasingly significant. Viscous damping, inertial mass, current loading...For the floating structures in deepwater, the coupling effects of the mooring lines and risers on the motion responses of the structures become increasingly significant. Viscous damping, inertial mass, current loading and restoring, etc. from these slender structures should be carefully handled to accurately predict the motion responses and line tensions. For the spar platforms, coupling the mooring system and riser with the vessel motion typically results in a reduction in extreme motion responses. This article presents numerical simulations and model tests on a new cell-truss spar platform in the State Key Laboratory of Ocean Engineering in Shanghai Jiaotong University. Results from three calculation methods, including frequency-domain analysis, time-domain semi-coupled and fully-coupled analyses, were compared with the experimental data to find the applicability of different approaches. Proposals for the improvement of numerical calculations and experimental technique were tabled as well.展开更多
Spar technology has been applied to the deep-sea oil and gas exploitation for several years. From the first generation of classic spar, the spar platform has developed into the second generation of truss spar and the ...Spar technology has been applied to the deep-sea oil and gas exploitation for several years. From the first generation of classic spar, the spar platform has developed into the second generation of truss spar and the latest cell spar. Owing to its favorable adaptability to wide range of water depth and benign motion performances, spar has aroused quite a lot of interests from oil companies, universities and research institutes. In the present paper, a new cell-truss spar concept, put forward by the State Key Laboratory of Ocean Engineering （SKLOE） at Shanghai Jiao Tong University, is studied both numerically and experimentally. The numerical simulation was conducted by means of nonlinear time-domain fully coupled analysis, and its results were compared to the experimental data. Whereafter, detailed analysis was carried out to obtain the global performances of＇ the new spar concept. Proposals for the improvement of numerical calculation and experimental technique were tabled meanwhile.展开更多
Recently, the spar platform concept develops quickly in the offshore oil and gas exploitations, especially in deep and ultra-deep water, owing to its benign motion performance, excellent stability and adaptation to wi...Recently, the spar platform concept develops quickly in the offshore oil and gas exploitations, especially in deep and ultra-deep water, owing to its benign motion performance, excellent stability and adaptation to wide range of water depth. Many new spar concepts have been put forward with the purpose of reducing fabrication difficulty and cost, while meeting the requirements of exploitation in the meantime Based on the aims mentioned above, a new spar concept was presented in this article and its hydrodynamics both in operating and survival conditions was studied by means of numerical simulation. Basic model tests were also conducted to calibrate the numerical approach. Following aspects are highlighted： （1） new spar concept, （2） global performance of the spar concept and （3） mooring line analysis.展开更多
针对DTU(Technical University of Denmark)10 MW风力机,使用FAST软件对典型海况下不同水动力分量作用下的半潜浮式风力机系统进行全耦合分析,包括仅一阶波浪力作用、一阶波浪力和采用Newman近似计算的二阶差频波浪力作用、一阶波浪力...针对DTU(Technical University of Denmark)10 MW风力机,使用FAST软件对典型海况下不同水动力分量作用下的半潜浮式风力机系统进行全耦合分析,包括仅一阶波浪力作用、一阶波浪力和采用Newman近似计算的二阶差频波浪力作用、一阶波浪力和全域二次传递函数(quadratic transfer functions,QTFs)计算的二阶差频波浪力作用、一阶波浪力和全域QTFs计算的二阶和频波浪力作用以及一阶波浪力和全域QTFs计算的完整二阶波浪力作用,以对比分析二阶差频、和频波浪力对超大型半潜浮式风力机动态响应的影响;基于风力机结构疲劳计算理论,分析二阶差频和频波浪力对风力机结构疲劳破坏的影响。研究发现:在极端海况下,二阶差频波浪力对平台运动响应,二阶差频及和频波浪力对半潜浮式风力机结构荷载和疲劳破坏均产生显著影响。此外,Newman近似方法明显低估二阶差频波浪力对半潜浮式风力机动态响应的影响。展开更多
基金the Major Fundamental Research Program of Science and Technology Commission of Shanghai Municipality (Grant No. 05DJ14001)the National High Technology Research and Development Program of China (863 Program, Grant No. 2006AA09A107)the State Key Laboratory of Ocean Engineering in Shanghai Jiaotong University are truly appreciated
文摘For the floating structures in deepwater, the coupling effects of the mooring lines and risers on the motion responses of the structures become increasingly significant. Viscous damping, inertial mass, current loading and restoring, etc. from these slender structures should be carefully handled to accurately predict the motion responses and line tensions. For the spar platforms, coupling the mooring system and riser with the vessel motion typically results in a reduction in extreme motion responses. This article presents numerical simulations and model tests on a new cell-truss spar platform in the State Key Laboratory of Ocean Engineering in Shanghai Jiaotong University. Results from three calculation methods, including frequency-domain analysis, time-domain semi-coupled and fully-coupled analyses, were compared with the experimental data to find the applicability of different approaches. Proposals for the improvement of numerical calculations and experimental technique were tabled as well.
基金This workis financially supported by the Major Fundamental Research Program of ScienceTechnology Commission of Shanghai Municipality(Grant No.05DJ14001)National High Technology Research and Development Programof China(863Program,Grant No.2006AA09A107).
文摘Spar technology has been applied to the deep-sea oil and gas exploitation for several years. From the first generation of classic spar, the spar platform has developed into the second generation of truss spar and the latest cell spar. Owing to its favorable adaptability to wide range of water depth and benign motion performances, spar has aroused quite a lot of interests from oil companies, universities and research institutes. In the present paper, a new cell-truss spar concept, put forward by the State Key Laboratory of Ocean Engineering （SKLOE） at Shanghai Jiao Tong University, is studied both numerically and experimentally. The numerical simulation was conducted by means of nonlinear time-domain fully coupled analysis, and its results were compared to the experimental data. Whereafter, detailed analysis was carried out to obtain the global performances of＇ the new spar concept. Proposals for the improvement of numerical calculation and experimental technique were tabled meanwhile.
基金the Major Fundamental Research Program of Science and Technology Commission of Shanghai Municipality (Grant No. 05DJ14001)the National High Technology Research and Development Program of China (863 Program, Grant No. 2006AA09A107).
文摘Recently, the spar platform concept develops quickly in the offshore oil and gas exploitations, especially in deep and ultra-deep water, owing to its benign motion performance, excellent stability and adaptation to wide range of water depth. Many new spar concepts have been put forward with the purpose of reducing fabrication difficulty and cost, while meeting the requirements of exploitation in the meantime Based on the aims mentioned above, a new spar concept was presented in this article and its hydrodynamics both in operating and survival conditions was studied by means of numerical simulation. Basic model tests were also conducted to calibrate the numerical approach. Following aspects are highlighted： （1） new spar concept, （2） global performance of the spar concept and （3） mooring line analysis.
文摘针对DTU(Technical University of Denmark)10 MW风力机,使用FAST软件对典型海况下不同水动力分量作用下的半潜浮式风力机系统进行全耦合分析,包括仅一阶波浪力作用、一阶波浪力和采用Newman近似计算的二阶差频波浪力作用、一阶波浪力和全域二次传递函数(quadratic transfer functions,QTFs)计算的二阶差频波浪力作用、一阶波浪力和全域QTFs计算的二阶和频波浪力作用以及一阶波浪力和全域QTFs计算的完整二阶波浪力作用,以对比分析二阶差频、和频波浪力对超大型半潜浮式风力机动态响应的影响;基于风力机结构疲劳计算理论,分析二阶差频和频波浪力对风力机结构疲劳破坏的影响。研究发现:在极端海况下,二阶差频波浪力对平台运动响应,二阶差频及和频波浪力对半潜浮式风力机结构荷载和疲劳破坏均产生显著影响。此外,Newman近似方法明显低估二阶差频波浪力对半潜浮式风力机动态响应的影响。
