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Citation:
　Zhengqiang Xu and Shan Huang.Numerical Investigation of Mooring Line Damping and the Drag Coefficients of Studless Chain Links[J].Journal of Marine Science and Application,2014,(1):76-84.[doi:1671-9433(2014)01-0076-09]
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Numerical Investigation of Mooring Line Damping and the Drag Coefficients of Studless Chain Links

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Title:
Numerical Investigation of Mooring Line Damping and the Drag Coefficients of Studless Chain Links
Author(s):
Zhengqiang Xu and Shan Huang
Affilations:
Author(s):
Zhengqiang Xu and Shan Huang
Dept. of Naval Architecture and Marine Engineering, University of Strathclyde, Glasgow, Henry Dyer Building, 100 Montrose Street, Glasgow G4 0LZ1, UK
Keywords:
CFD;  drag coefficient;  low frequency motion;  mooring line damping;  chain links;  offshore floating platforms
分类号:
-
DOI:
1671-9433(2014)01-0076-09
Abstract:
The chain/wire rope/chain combination is a common choice for mooring offshore floating platforms. However, data of the drag coefficients of chain links are rather limited, resulting in uncertainties with the calculations of the drag force, and hence the damping of the mooring system. In this paper, the importance of the selection of the drag coefficient is first investigated. The computational fluid dynamics (CFD) method is then used to determine the drag coefficients of a studless chain under steady flows. Numerical model validation is first completed by simulating a smooth circular cylinder under steady flows. In particular, the performance of different turbulence models is assessed through the comparisons between the calculations and the experimental results. The large eddy simulation (LES) model is finally selected for the simulation of steady flows past a chain. The effects of the Reynolds number on the drag coefficient of a stud-less chain is also studied. The results show that the calculated drag coefficients of a stud-less chain are fairly consistent with the available experimental data.

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Last Update: 2014-11-04