Hydrodynamic Analysis of Floating Offshore Wind Turbine With Different Numbers of Offset Columns

Currently, there is a strong interest to develop offshore wind energy because of the great impact of greenhouse gases and the energy crisis. Extraordinary endeavors have been dedicated to creating floating offshore wind turbine (FOWT) innovations such as the DeepCwind semi-submersible FOWT that can be relied upon to harness wind energy in deep water. However, DeepCwind structure faces a significant surge motion limiting the operational time. Therefore, this paper presents three different configurations for the DeepCwind semi-submersible FOWT by varying the number of offset columns from three to five columns to improve the wave resistance ability. Hydrodynamic analysis is carried out to figure and compare the performance of these platforms via the ANSYS-AQWA tool. The free-decay test has shown that the natural frequency is affected by the number of offset columns. The results of statistics on regular waves and irregular waves have shown that the surge response is inversely proportional to the number of offset columns; the statistics decrease with the increase of the offset columns number, while the impacts of increasing offset columns are negligible for the heave and pitch motions.