EFFECT OF WIND-WAVE MISALIGNMENT ON DYNAMIC RESPONSE OF FIXED-BOTTOM OFFSHORE WIND TURBINE

Abstract

 The misalignment between wind and waves is an important factor in the design of offshore wind turbines (OWTs) and the dynamic response of OWT is often evaluated assuming that wind and waves act from the same direction. However, the conditions under which such assumptions hold are limited in the real sea and the response may be underestimated depending on meteorological and oceanographic conditions. The purpose of this study is to investigate the effect of wind-wave misalignment on the dynamic response of a large-scale fixed-bottom OWT. As a result, it was found that the effect of wind-wave misalignment is more pronounced when the waves act in the direction directly opposite to the wind direction (back side of the wind turbine rotor face) for the fore-aft direction and from the side of the turbine for the side-side direction, and that when constructing fixed-bottom OWTs in shallow water, it is important to fully consider not only to wave characteristics but also to the directionality of wind and waves.