Wind tunnel investigation of the aerodynamic response of two 15 MW floating wind turbines

Abstract. The aerodynamics of floating turbines is complicated by large motions which are permitted the foundation, and interaction between turbine, wind, wake not yet fully understood. object this paper a wind tunnel campaign finalized at characterizing aerodynamic response 1:100 scale model IEA 15 MW subjected to imposed platform motion. turbine studied focusing on thrust force, torque, 2.3D downwind rotor. Harmonic motion in surge, sway, roll, pitch, yaw directions with several frequencies amplitudes, selected be representative two developed within COREWIND project. Thrust torque show large-amplitude oscillations surge pitch motion, main effect an apparent speed; negligible other motions, alter direction. measured experiment compared predictions quasi-steady model, often used for control-related tasks. agreement good case low-frequency but some differences seen case. predictive wave-frequency where blade unsteadiness may take place. Wake was imposing five frequency equal wave frequency. axial speed slightly lower fixed turbulence kinetic energy too. Wave-frequency seems produce more stable flow mixing.