A Contribution on Quasi-Static Mooring Line Damping
- 12 October 1999
- journal article
- Published by ASME International in Journal of Offshore Mechanics and Arctic Engineering
- Vol. 122 (2), 125-133
- https://doi.org/10.1115/1.533734
Abstract
Since the pioneering work of Huse (1986, “Influence of Mooring Line Damping Upon Rig Motions,” Proc., 18th OTC Conference), it is well known that mooring lines may account for a large fraction of the overall damping present in a moored floating structure. This paper is concerned with the mooring line damping induced by the low-frequency, quasi-static, horizontal motion of the mooring line fairlead. The main advantage of the quasi-static approach is that it is much faster than the more accurate finite element methods, and, secondly, that it does not require any finite element modeling skills. A new formulation is proposed and is compared to the results of Liu et al. (1998, “Improvement on Huse’s Model for Estimating Mooring Cable-Induced Damping,” Proc., 17th OMAE Conference), as well as to time domain results obtained with FLEXRISER. The improvement with respect to the previous quasi-static methods is quite notable and our results are closer to FLEXRISER predictions. Finally, quasi-static results are compared to mooring line damping values measured during model tests for full mooring systems. The agreement between the two is very encouraging and suggests that the simpler quasi-static approach may, in some circumstances, be a valuable substitute for the more complex and time-consuming numerical tools. [S0892-7219(00)00102-3]Keywords
This publication has 9 references indexed in Scilit:
- Comparative study on mooring line dynamic loadingMarine Structures, 1999
- Mooring-induced dampingOcean Engineering, 1995
- The Influence of Mooring Line Damping on the Prediction of Low-Frequency Vessel Motions at SeaPublished by Society of Petroleum Engineers (SPE) ,1991
- New Developments in Prediction of Mooring System DampingPublished by Society of Petroleum Engineers (SPE) ,1991
- Slow drift damping due to drag forces acting on mooring linesOcean Engineering, 1991
- The Contribution of Hydrodynamic Damping Induced by Mooring Chains on Low-Frequency Vessel MotionsPublished by Society of Petroleum Engineers (SPE) ,1990
- Mooring Line Damping Due to First- and Second-Order Vessel MotionPublished by Society of Petroleum Engineers (SPE) ,1989
- Practical Estimation of Mooring Line DampingPublished by Society of Petroleum Engineers (SPE) ,1988
- Influence Of Mooring Line Damping Upon Rig MotionsPublished by Society of Petroleum Engineers (SPE) ,1986