Investigation of Buoy Size and Location on Hydrodynamic Response and Mooring Tension of the DeepCwind Floating Wind Turbine

Arman Aghaei Ganjgani¹, Hamid Reza Ghafari¹, Hassan Ghassemi^1, and Mahmoud Ghiasi¹

¹Department of Maritime Engineering, Amirkabir University of Technology, Tehran, Iran

Cite this paper:
Arman Aghaei Ganjgani, Hamid Reza Ghafari, Hassan Ghassemi and Mahmoud Ghiasi. Investigation of Buoy Size and Location on Hydrodynamic Response and Mooring Tension of the DeepCwind Floating Wind Turbine. American Journal of Civil Engineering and Architecture. 2022; 10(1):1-7. doi: 10.12691/ajcea-10-1-1

Abstract

This paper investigates the effect of different sizes and locations of the buoy on the dynamic response of the floating platform. The full-scale of the OC4-DeepCwind semi-submersible floating offshore wind turbine (FOWT) platform was analyzed using the boundary element method (BEM) in ANSYS-AQWA software, considering regular wave conditions. Platform motions and mooring line tension in the surge, heave, and pitch are presented and discussed in time and frequency domains. Validation was carried out by comparison of the platform motion RAO (response amplitude operator) and fairlead tension RAO magnitudes in the surge, heave, and pitch between numerical and experimental data under seven sea states' regular waves. Four different buoy diameters and its locations (B1, B2, B3, and B4) have been considered. The results show that increasing the buoy size leads to an increase in surge motion, while the amplitude of semi-submersible decreases in heave motion. Also, in the pitch motion, it is reduced for B1 and B2, while an increase was found for B3 and B4. In addition, increasing the distance of buoy from the platform leads to an increase in the surge motion response while it is reduced for that of the heave response.

Keywords:
DeepCwind platform BEM buoys catenary mooring line

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