Experimental and Numerical Analysis of a 10 MW Floating Offshore Wind Turbine in Regular Waves

Hyeonjeong Ahn,Hyunkyoung Shin

doi:10.3390/en13102608

Abstract

Floating offshore wind turbines (FOWTs) experience fluctuations in their platforms, owing to the various wave and wind conditions. These fluctuations not only decrease the output of the wind power generation system, but also increase the fatigue load of the structure and various equipment mounted on it. Therefore, when designing FOWTs, efficient performance with respect to waves and other external conditions must be ensured. In this study, a model test was performed with a 10 MW floating offshore wind turbine. The model test was performed by scaling down a 10 MW FOWT model that was designed with reference to a 5 MW wind turbine and a semisubmersible platform by the National Renewable Energy Laboratory and the DeepCwind project. A scale ratio of 1:90 was used for the model test. The depth of the East Sea was considered as 144 m and, to match the water depth with the geometric similarity of mooring lines, mooring tables were installed. The load cases used in the model test are combined environmental conditions, which are combined uniform wind, regular waves and uniform current. Especially, Model tests with regular waves are especially necessary, because irregular waves are superpositions of regular waves with various periods. Therefore, this study aimed to understand the characteristics of the FOWTs caused by regular waves of various periods. Furthermore, in this model test, the effect of current was investigated using the current data of the East Sea. The results obtained through the model tests were the response amplitude operator (RAO) and the effective RAO for a six degrees-of-freedom motion. The results obtained from the model tests were compared with those obtained using the numerical simulation. The purpose of this paper is to predict the response of the entire system observed in model tests through simulation.

Highlights

In recent decades, rising oil prices, climate change, air pollution, and water shortages have resulted in increased energy concerns
The results obtained through the model tests were the response amplitude operator (RAO)
The tests were The performed by performed pushing down the structure the structure from a nearby carriage, and a tuning process was performed in the numerical simulation, from a nearby carriage, and a tuning process was performed in the numerical simulation, such as such minor adjustments of stiffness and damping of the [25]

Summary

Introduction

In recent decades, rising oil prices, climate change, air pollution, and water shortages have resulted in increased energy concerns. Wind power has been used for developing pioneering renewable technologies for decades. With the development of wind power technology, research on large-scale wind turbines and offshore wind turbines is becoming more active. A representative example is the installation of a 12-MW Haliade-X offshore wind turbine prototype at the port of Rotterdam, the Netherlands this year by GE Renewable. It is the largest and most powerful offshore wind turbine in the world, with a 220-m rotor and a 107-m blade. Many studies are underway to reduce the mass of the tophead as the wind turbine becomes larger, such as by the use of superconducting generators [1,2], the use of CFRP blades [3], and optimization of the rotor design [4,5]

Objectives

Results

Conclusion