Session: 09-01-02 Wind Energy: Aero-hydrodynamics 2

Paper Number: 123167

123167 - Dynamic Responses of the Tower and Blades on a Spar-Type Floating Wind Turbine Under Freak Waves With Different Properties 

A floating offshore wind turbine would be subjected to various abnormal waves. Among them, the freak waves which have high energy may suddenly enlarge the stress and deformation of the upper flexible structures such as blades and tower. The numerical model of a Spar-type floating wind turbine is established, the freak wave is numerically generated and modulated based on the phase angle modulation method. Four types of modulated freak waves with different properties are obtained by quantitatively modulating the wave profile via the corresponding decision parameters. The dynamic performances of the SFWT under the freak waves are simulated in the time domain, and the internal load and deformations of the SFWT blade and tower are qualitatively and quantitatively analyzed. According to the results, it shows that the structural loads and deformations of the blade and tower have different low-frequency response amplifications. The blade edgewise deformations are significant while the tower resonates with the floating foundation. The results on the MFWs effect indicate that the deformation, bending moment, shear force and torque of the tower and blade increase significantly with the fluctuation degree changing wave enlargement. Among them, the changes of bending moment are the most significant. The torque decreases with the expansion of the previous height changing wave and impact height changing wave. The next height changing wave has little amplification effect on any load responses. Furthermore, the influence of wave properties on the blade tip deformation is almost instantaneous, while the effect on the bending moment has a lag in the time domain.

Presenting Author: Yan Li Tianjin University

Presenting Author Biography: Associate Prof. @ Tianjin University

Authors:

Yan Li Tianjin University
Haoran Li Tianjin University
Yiwen Cui Tianjin University
Ouming Su Tianjin University
Guoyan Li Tianjin University
Yougang Tang Tianjin University