Naslov
Improved dynamics model for synthetic fibre mooring lines

Autori
Ćatipović, Ivan ; Alujević, Neven ; Rudan, Smiljko ; Slapničar, Vedran

Vrsta, podvrsta i kategorija rada
Radovi u zbornicima skupova, cjeloviti rad (in extenso), znanstveni

Izvornik
Proceedings of International Conference on Ships and Offshore Structures - ICSOS 2021, Hamburg, Germany / Ehlers, Sören ; Paik, Jeom - , 2021, 1-17

Skup
International Conference on Ships and Offshore Structures (ICSOS 2021)

Mjesto i datum
Hamburg, Njemačka, 06.09.2021. - 08.09.2021

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
synthetic fibre ropes ; mooring lines dynamics ; stiffness ; damping ; added mass ; nonlinear finite element method

Sažetak
Synthetic fibre ropes are currently widely accepted in the design of mooring systems for traditional offshore platforms used for oil and natural gas production, as well as for objects intended for harvesting renewable marine energy sources, such as wind or waves. These kinds of ropes are more easily handled and offer better strength to weight ratio than steel wire ropes or chains. Thus, their use in the future will certainly grow. During exploitation, synthetic ropes undergo large axial deformations, i.e. the elongation of the ropes is relatively high, reaching 30% or 40%, depending on the rope type. In current practices, the axial deformation is neglected in calculation of mooring lines motions. In this study a new motion equation is proposed for solving mooring line dynamics. This improved equation contains additional terms that introduce the impact of axial deformations to stiffness forces and hydrodynamic reactions, as well as to wave- induced loads acting directly on the mooring line. Two new alternative formulations of the mooring line finite element are offered as a solution to the presented problem. Hydrodynamic reactions are included, by Morison equation, in the finite element but with additional members for incorporating the influence of axial deformation onto the added mass and damping. A comparison between the improved models and the current practice is conducted. Simple mooring lines that can be analytically described were used as a basis for the comparisons. The improved models achieve significantly better correlations with the analytical results.

Izvorni jezik
Engleski

Znanstvena područja
Brodogradnja

POVEZANOST RADA