Study on vibration of the offshore large-scale wind turbine blade under fluid structure interaction at different wind speeds

The research object is based on the 1.5 MW large offshore wind turbine blade. A theoretical model for describing the geometrical non-linearity vibration behavior under the condition of fluid structure interaction (FSI) was established, the entity modeling of the wind turbine blade was achieved by using Pro/E, and the numerical simulation under unidirectional FSI (UFSI) and bidirectional FSI (BFSI) was carried out at different wind speeds by ANSYS and CFX softwares. The results indicate that the high pressure region and low pressure region respectively appear on the windward side and the leeward side of the blade, and the strength of wind pressure distribution under BFSI is lower than the one under UFSI. It is also found that the maximum brandish displacement locates in the blade tip and the maximum Mises stress occurs in the middle of blade at different wind speeds. Furthermore, the effect of BFSI on the wind blade vibration is much more obvious with the increase of wind speed. Finally, compared with the amplitude calculated by UFSI, the analytical method of BFSI truly reveals the aeroelastic characteristics of the blade under complex offshore wind conditions