Volume 17, Issue 34 (12-2021)
Marine Engineering 2021, 17(34): 85-98 |
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1- Marine engineering faculty, Chabahar Maritime University
Abstract: (2088 Views)
The mooring design of floating structures is one of the important parts in the design process of offshore structures. To design and evaluate the performance of mooring lines, criteria such as ultimate strength and fatigue have been defined. In real conditions, mooring forces are random variables, so to check the strength, the statistical distribution of mooring forces under the influence of environmental condition must be calculated at first. In this article, a statistical study of the mooring force of a semi-submersible offshore wind turbine, which is stabled by three catenary-chain mooring lines, has been considered. Hydrodynamic analysis of the structure was performed by ANSYS-AQWA software and the environmental characteristics of the area were extracted from the DNVGL standard for the Mediterranean Sea. During the life of the structure, due to corrosion, the diameter of the mooring chain decreases. Therefore, in this research, the condition of the mooring lines from the perspective of tensile forces has been investigated by considering the corrosion at a constant annual rate. During the life of the structure, due to corrosion and as a result the reduction of the axial stiffness, the tension of the mooring lines will be reduced. This amount of reduction for the critical mooring line in 10-year intervals of its 30-year lifetime is 5.4, 13.1 and 21.3 percent, respectively.
Keywords: Floating offshore wind turbine, Hydrodynamic analysis, Mooring lines, Mooring tension, Statistical distribution
Type of Study: Research Paper |
Subject:
Offshore Hydrodynamic
Received: 2021/06/27 | Accepted: 2021/10/26
Received: 2021/06/27 | Accepted: 2021/10/26
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