Underwater Radiated Noise Analysis of Fixed Offshore Wind Turbines Considering the Acoustic Properties of the Western Coast of the Korean Peninsula

With continued technological advancements, the sizes of fixed-bottom offshore wind turbines have increased, resulting in increased operational noise levels. In this study, we investigated the underwater radiated noise generated by wind turbine operation along the western coast of the Korean Peninsula using numerical simulations. Using the OpenFAST software, a load analysis of the National Renewable Energy Laboratory 5 MW reference turbine with a jacket substructure was conducted for the various wind speeds defined in Design Load Case 1.2. The load analysis results and gear mesh frequency components were applied as excitation forces in a finite-element-method-based structural–acoustic coupled analysis model to evaluate underwater radiated noise, incorporating the acoustic properties of the seabed along the western coast of the Korean Peninsula and dynamic state of the sea surface. The numerical results were subsequently compared with experimental measurements of the operational noise from wind turbines supported by jacket substructures. The results indicated that, excluding certain frequency bands, the spectral levels were similar across the frequency spectrum.