Hull/mooring/riser coupled dynamic analysis and sensitivity study of a tanker-based FPSO   总被引：2，自引：0，他引：2  

Arcandra Tahar  M. H. Kim   《Applied Ocean Research》2003,25(6):367-382

A computer program is developed for hull/mooring/riser coupled dynamic analysis of a tanker-based turret-moored FPSO (Floating Production Storage and Offloading) in waves, winds, and currents. In this computer program, the floating body is modeled as a rigid body with six degrees of freedom. The first- and second-order wave forces, added mass, and radiation damping at various yaw angles are calculated from the second-order diffraction/radiation panel program WAMIT. The wind and current forces for various yaw angles of FPSO are modeled following the empirical method suggested by OCIMF (Oil Company International Marine Forum).

The mooring/riser dynamics are modeled using a rod theory and finite element method (FEM), with the governing equations described in a generalized coordinate system. The dynamics of hull, mooring lines, and risers are solved simultaneously at each time step in a combined matrix for the specified connection condition. For illustration, semi-taut chain-steel wire-chain mooring lines and steel catenary risers are employed and their effects on global FPSO hull motions are investigated. To better understand the physics related to the motion characteristics of a turret-moored FPSO, the role of various hydrodynamic contributions is analyzed and assessed including the effects of hull and mooring/riser viscous damping, second-order difference-frequency wave-force quadratic transfer functions, and yaw-angle dependent wave forces and hydrodynamic coefficients. To see the effects of hull and mooring/riser coupling and mooring/riser damping more clearly, the case with no drag forces on those slender members is also investigated. The numerical results are compared with MARIN's wave basin experiments.  相似文献   

Nonlinear Dynamic Analysis of Flexible Marine-Risers     

Chen Jiajing  Wang Dongjiao Professor  South China University of Technology  Guangzhou PhD Student  Hong Kong Polytechnic  Formerly  South China University of Technology  Guangzhou 《中国海洋工程》1991,(4)

A nonlinear dynamic analysis model is estabilished on the basis of "lumped mass" approach, which takes the influence of the fluid flow within the pipe into consideration. Numerical results are compared with the published works, and the effects of internal fluid flow, internal pressure, dyanmics as well as the nonlinear characteristics on the behavior of flexible risers are discussed. From this work, some useful conclusions are drawn.  相似文献   

Nonlinear Behaviour of Coflexip Risers     

Kamal Zare  T. K. Datta 《中国海洋工程》2001,(4):479-490

A modified Newton-Raphson iterative technique is formulated for obtaining the static configuration of the Lazy "S" flexible marine riser between the floater and mid-arch buoy under its submerged self weight and the applied top tension. The geometrically non-linear problem is solved by finite difference with the above technique. The problem is formulated as a regular boundary value problem with specified moments and deflections at both ends. Usually the bending stiffness of the flexible riser made of Coflexip pipe is very low. By use of the above analysis, several flexible riser configurations are analyzed and their characteristic behaviors are investigated. Also, changes in the riser characteristics due to quasi-static motion of the floater end are estimated for the safety of the riser layout.  相似文献   

Genetic mapping and QTL analysis for body weight in Jian carp (Cyprinus carpio var. Jian) compared with mirror carp (Cyprinus carpio L.)     

顾颖  鲁翠云  张晓峰  李超  俞菊华  孙效文 《中国海洋湖沼学报》2015,33(3):636-649

We report the genetic linkage map of Jian carp(C yprinus carpio var. Jian). An F1 population comprising 94 Jian carp individuals was mapped using 254 microsatellite markers. The genetic map spanned 1 381.592 c M and comprised 44 linkage groups,with an average marker distance of 6.58 c M. We identified eight quantitative trait loci(QTLs) for body weight(BW) in seven linkage groups,explaining 12.6% to 17.3% of the phenotypic variance. Comparative mapping was performed between Jian carp and mirror carp( Cyprinus carpio L.),which both have 50 chromosomes. One hundred and ninety-eight Jian carp marker loci were found in common with the mirror carp map,with 186(93.94%) showing synteny. All 44 Jian carp linkage groups could be one-to-one aligned to the 44 mirror carp linkage groups,mostly sharing two or more common loci. Three QTLs for BW in Jian carp were conserved in mirror carp. QTL comparison suggested that the QTL confidence interval in mirror carp was more precise than the homologous interval in Jian carp,which was contained within the QTL interval in Jian carp. The syntenic relationship and consensus QTLs between the two varieties provide a foundation for genomic research and genetic breeding in common carp.  相似文献   

国外区域联系研究综述   总被引：19，自引：0，他引：19  

朱英明  姚士谋 《世界地理研究》2001,10(2):16-24

区域联系是提高区域乃至国家竞争力的基本要求，因此，国外对区域联系研究为重视，本文对国外区域联系研究的主要方面进行了综述，就研究内容而言，包括：地区联系、中心地联系、城市等级联系、商品流联系、相互作用联系、扩散联系、模型模拟间接反映的区域联系等七个方面，就时序发展看，有的区域联系的时间界限非常清晰，但大多数区域联系内容是交叉和重叠的，贯穿于各个时期。  相似文献   

正断层三维生长和连接过程研究：以南海北部陆丰凹陷为例     

代向明  李志刚  孙闯  李立国  王伟涛  惠格格  梁浩  张逸鹏  李琳琳  闫永刚  许斌斌  李冠华 《地质学报》2022,96(6):1922-1936

正断层生长和侧向连接是最基本的三维地质构造问题，深入剖析其三维时 空演化过程对理解沉积盆地内正断层系统的形成与演化至关重要。 南海扩张时间和影响范围一直是国内外地学界研究的热点问题之一。南海北部珠江口盆地陆丰凹陷发育大量正断层，并覆盖有高精度二维地震反射剖面，成为研究上述问题的理想地区之一。本研究以陆丰凹陷为研究对象，开展三维构造解析和建模研究，为正断层系统三维时 空演化过程提供一个实例。研究结果表明：陆丰凹陷主控断层F1的生长和连接过程主要分三个阶段：晚白垩世—早古新世，两条断层分别形成并以孤立断层模式分别向两侧生长；早古新世—早渐新世，断层发生侧向连接作用合并为F1断层，连接处发育侧断坡；晚渐新世—中中新世，F1断层继续向两侧生长。基于F1断层定量分析（生长指数和断距），发现F1断层活动强度表现为先增加然后突然降低，其转折时间对应于T60界面，~23 Ma，较好地对应了西北次海盆扩张终止时间，说明南海北部扩张已经影响到陆丰凹陷。结合前人对珠江口盆地构造变形和演化研究，初步认为南海北部扩张波及的范围已跨过陆丰凹陷向大陆方向继续延伸，其北部边界可能对应于华南大陆南缘的滨海断裂带。本研究可为正断层系统三维生长过程研究提供案例，同时为南海扩张过程研究提供基础数据支撑。  相似文献   

多尺度视角下长株潭城市群工业旅游空间布局及联动模式   总被引：1，自引：0，他引：1  

唐健雄  马梦瑶 《地理科学》2021,41(8):1428-1436

采用最邻近指数、泰森多边形、核密度估计、缓冲区分析等方法,基于城市群、县（市）、地区等多尺度对长株潭城市群不同类型工业旅游的空间布局特征及联动模式进行系统研究。结果表明：① 长株潭城市群工业旅游可划分为工业旅游示范点、工业遗产和工业区等3种类型,空间分布上均呈现为集聚态势,且总体集聚程度较强,具体表现为：工业旅游示范点>工业遗产>工业区。② 工业旅游形成“中心集聚?外围分散”的空间布局,分布密度由城市群中部向周边递减,中心城市向县、县级市递减。③ 从多尺度视角来看,工业旅游空间布局在城市群尺度上呈“团状”,县市尺度上呈“孤岛状”,地区尺度呈“块斑状”。基于以上结论,提出工业旅游的点?轴联动、集聚联动和一体化联动模式。  相似文献   

Along‐strike structural linkage and interaction in an active thrust fault system: A case study from the western Sichuan foreland basin,China     

Gonghua Song  Maomao Wang  Danqi Jiang  Zhuxin Chen  Bing Yan  Wang Feng 《Basin Research》2021,33(1):210-226

Along‐strike structural linkage and interaction between faults is common in various compressional settings worldwide. Understanding the kinematic history of fault interaction processes can provide important constraints on the geometry and evolution of the lateral growth of segmented faults in the fold‐and‐thrust belts, which are important to seismic hazard assessment and hydrocarbon trap development. In this study, we study lateral structural geometry (fault displacement and horizon shortening) of thrust fault linkages and interactions along the Qiongxi anticline in the western Sichuan foreland basin, China, using a high‐resolution 3D seismic reflection dataset. Seismic interpretation suggests that the Qiongxi anticline can be related to three west‐dipping, hard‐linked thrust fault segments that sole onto a regional shallow detachment. Results reveal that the lateral linkage of fault segments limited their development, affecting the along‐strike fault displacement distributions. A deficit between shortening and displacement is observed to increase in linkage zones where complex structural processes occur, such as fault surface bifurcation and secondary faulting, demonstrating the effect of fault linkage process on structural deformation within a thrust array. The distribution of the geometrical characteristics shows that thrust fault development in the area can be described by both the isolated fault model and the coherent fault model. Our measurements show that new fault surfaces bifurcate from the main thrust ramp, which influences both strain distribution in the relay zone and along‐strike fault slip distribution. This work fully describes the geometric and kinematic characteristics of lateral thrust fault linkage, and may provide insights into seismic interpretation strategies in other complex fault transfer zones.  相似文献   

安徽省运输联系空间格局演化与经济发展的关系分析     

关颖  曹有挥  梁双波 《世界地理研究》2007,16(1):76-82

根据1985年-2003年17个地市的客、货运量资料，采用差异指数、非均衡指数、交通拉动系数等分析技术，对安徽省空间运输联系特征及其演化规律、与经济发展的关系进行研究。安徽省高速公路沿线地区客、货运增长较快；客运向合肥为中心的相邻地市集中分布，货运则呈向高速沿线地区分布的格局，但总体趋于均衡分布态势。空间运输联系与经济发展关系尚不显著，合巢芜宣经济带客、货运增长均超过沿江经济带。  相似文献   

Antithetic fault linkages in a deep water fold and thrust belt   总被引：4，自引：0，他引：4  

Simon Higgins  Richard J. Davies  Benjamin Clarke   《Journal of Structural Geology》2007,29(12):1900-1914

Deep water fold and thrust belts consist of both forethrusts and backthrusts that can link along strike to form continuous folds in the overburden. The interaction of faults of opposing dip are termed ‘antithetic thrust fault linkages’ and share the common feature of a switch in vergence of overlying hangingwall anticlines. Using three-dimensional seismic data, on the toe-of-slope of the Niger Delta, linkages are classified into three distinct structural styles. This preliminary classification is based on the vertical extent of faulting within a transfer zones relative to the branch line of the antithetic faults. The stratigraphic level of the lateral tip of the fault, the shape of lateral tip region of a fault plane and the stratal deformation within the transfer zones is also distinctive in each type of fault linkage. A Type 1 linkage comprises faults that overlap exclusively above the level of the branch line. A ‘pop-up’ structure forms within the transfer zone with sediments below remaining planar. The lower tip lines of faults climb stratigraphically towards the linkage zone creating asymmetric, upward-tapering lateral tip regions. In Type 2 linkages fault overlap occurs lower than the level of the branch line such that lateral fault tips are located within the footwall of the counterpart fault. Faulting is thus limited to the deeper section within the transfer zone and creates unfaulted, symmetric, bell-shaped folds in the overburden. Upper tip lines of faults lose elevation within the transfer zone creating asymmetric, downwards-tapering lateral tip regions. In Type 3 linkages both faults continue above and below the branch line within the transfer zone resulting in cross-cutting fault relationships. Horizon continuity across the folds, through the transfer zones, varies significantly with depth and with the type of fault intersection.  相似文献