Analysis of Nonlinear Destructive Interaction between Wind and Wave Loads Acting on the Offshore Wind Energy Converter based on the Hydraulic Model Test

Title & Authors
Analysis of Nonlinear Destructive Interaction between Wind and Wave Loads Acting on the Offshore Wind Energy Converter based on the Hydraulic Model Test
Cho, Yong Jun; Yang, Kee Sok;

Abstract
In order to quantitatively estimate the nonlinear destructive interaction of wave load with wind load, which is very vital for the optimal design of offshore wind energy converter, we carried out a hydraulic model test and wind tunnel test. As a substructure of offshore wind energy converter, we would deploy the monopile, which is popular due to its easiness in construction. Based on the simulation using Monte Carlo simulation using Kaimal spectrum and cross spectrum, the instantaneous maximum wind velocity is adjusted to 10 m/s. And, considering the wave conditions of the Western Sea where a pilot wind farm is planned to be constructed, $\small{H_s=0.1m}$, 0.15 m, 0.2 m is carefully chosen. It turns out that the nonlinear destructive interaction between the wind and wave loads acting on the offshore wind energy converter is more clearly visible at rough seas rather than at mild seas, which strongly support our deduction that a Large eddy, a swirling vortex developed near the bumpy water surface in the opposite direction of the wind, is the driving mechanism underlying nonlinear destructive interaction between the wind and wave loads.
Keywords
nonlinear destructive interaction between wave and wind load;Large eddy;Kaimal spectrum;JONSWAP spectrum;aeroelastic analysis;hydroelastic analysis;
Language
Korean
Cited by
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