Fatigue Assessment of Monopile Offshore Wind Turbine Underthe Wave Loading in Chabahar Bay

Wind turbines like other Offshore structures face severe challenges from fatigue because of enduring wave and wind loading. Wave and wind forces and their direction can drastically impact these structures. Three wave theories including Airy, 5th-order Stokes, and Stream function were employed to evaluate structural responses in this study. The 5-MW monopile wind turbine in the Arabian Sea, at a depth of 23 meters, was simulated numerically throughout 10 years of available wave data. The frequency domain method was applied to the structure. Three strategies were employed to decide important wave frequencies considering fatigue index; 1-Probability of wave occurrence, 2-Static transfer function and 3-Analysis of mode shapes and 188 essential frequencies were extracted, then used for fatigue calculation in SACS software. In the modal analysis, displacement, velocity, acceleration and base shear transfer function were obtained. The findings confirmed that the maximum effect on fatigue damage is attributed to the 5th-order Stokes theory, the stream function and the Airy theory respectively.

Fatigue Assessment of Monopile Offshore Wind Turbine Underthe Wave Loading in Chabahar Bay Keywords:

Fatigue , Offshore Wind Turbine , Wind-Wave Misalignment , Wave Theory , Wave spectrum.