A theory and numerical tool are developed for the coupled-dynamic analysis of a deepwater floating platform with polyester mooring lines. The formulas allow relatively large elongation and nonlinear stress-strain relationships, as typically observed in polyester fibers. The mooring-line dynamics are based on a rod theory and the FEM (finite element method), with the governing equations described in a generalized coordinate system. The original rod theory (Nordgren, R.P., 1974. On Computation of the Motion of Elastic Rods. Journal of Applied Mechanics, 41, 777-780) is generalized to allow larger elongation and nonlinear stress-strain relationship. The dynamic modulus of polyester is modeled following an empirical regression formula suggested by (Bosman, R.L.M., Hooker, J., 1999. The Elastic Modulus Characteristic of Polyester Mooring Ropes. In: Proceedings of the Offshore Technology Conference, OTC 10779. Houston, Texas), in which the axial stiffness is not constant, but depends on loading conditions. Two case studies, the static and dynamic behavior of a tensioned buoy and a classic spar with polyester mooring lines, are conducted. The time-domain simulation results are systematically compared with those from the original rod theory. The effects of large elongation and nonlinear stress-strain relations are separately assessed. It is seen that the mean offset, motions, and tension with polyester lines can be different from those by original rod theory with linear elastic lines.
Coupled-dynamic analysis of floating structures with polyester mooring lines
Gekoppelte dynamische Analyse von schwimmenden Strukturen mit Festmacherleinen aus Polyester
Ocean Engineering ; 35 , 17-18 ; 1676-1685
2008
10 Seiten, 17 Quellen
Article (Journal)
English
Installation of mooring lines for floating offshore structures
European Patent Office | 2024
Nonlinear identification of mooring lines in dynamic operation of floating structures
Tema Archive | 2004
|Installation of mooring lines for floating offshore structures
European Patent Office | 2023
|Reliability analysis of mooring lines for floating structures using ANN-BN inference
SAGE Publications | 2021
|Creep and relaxation of polyester mooring lines
Tema Archive | 2000
|