Full time-domain nonlinear coupled dynamic analysis of a truss spar and its mooring/riser system in irregular wave  

作　　者：YANG MinDong TENG Bin XIAO LongFei NING DeZhi SHI ZhongMin QU Yan 

机构地区：[1]Guangdong Electric Power Design Institute,China Energy Engineering Group Co. Ltd. [2]Department of Ocean Engineering, Ocean University of China [3]State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology [4]State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University [5]Technology Research Department,China National Offshore Oil Corporation

出　　处：《Science China(Physics,Mechanics & Astronomy)》2014年第1期152-165,共14页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National High Technology Research and Development Program of China(Grant No.2006AA09A109-3);the Important National Science&Technology Specific Projects(Grant No.2008ZX05026-06-02)

摘　　要：A new full time-domain nonlinear coupled method has been established and then applied to predict the responses of a Truss Spar in irregular wave. For the coupled analysis, a second-order time-domain approach is developed to calculate the wave forces, and a finite element model based on rod theory is established in three dimensions in a global coordinate system. In nu- merical implementation, the higher-order boundary element method （HOBEM） is employed to solve the velocity potential, and the 4th-order Adams-Bashforth-Moultn scheme is used to update the second-order wave surface. In deriving convergent solu- tions, the hull displacements and mooring tensions are kept consistent at the fairlead and the motion equations of platform and mooring-lines/risers are solved simultaneously using Newmark-fl integration scheme including Newton-Raphson iteration. Both the coupled quasi-static analysis and the coupled dynamic analysis are performed. The numerical simulation results are also compared with the model test results, and they coincide very well as a whole. The slow-drift responses can be clearly ob- served in the time histories of displacements and mooring tensions. Some important characteristics of the coupled responses are concluded.A new full time-domain nonlinear coupled method has been established and then applied to predict the responses of a Truss Spar in irregular wave.For the coupled analysis,a second-order time-domain approach is developed to calculate the wave forces,and a finite element model based on rod theory is established in three dimensions in a global coordinate system.In numerical implementation,the higher-order boundary element method(HOBEM)is employed to solve the velocity potential,and the 4th-order Adams-Bashforth-Moultn scheme is used to update the second-order wave surface.In deriving convergent solutions,the hull displacements and mooring tensions are kept consistent at the fairlead and the motion equations of platform and mooring-lines/risers are solved simultaneously using Newmark-integration scheme including Newton-Raphson iteration.Both the coupled quasi-static analysis and the coupled dynamic analysis are performed.The numerical simulation results are also compared with the model test results,and they coincide very well as a whole.The slow-drift responses can be clearly observed in the time histories of displacements and mooring tensions.Some important characteristics of the coupled responses are concluded.

关 键 词：coupled method full time-domain SECOND-ORDER truss spar rod theory irregular wave 

分 类 号：O302[理学—力学] O241.82