OC6 project Phase III: validation of the aerodynamic loading on a wind turbine rotor undergoing large motion caused by a floating support structure

Abstract. This paper provides a summary of the work done within Phase III Offshore Code Comparison Collaboration, Continued, with Correlation and unCertainty (OC6) project, under International Energy Agency Wind Technology Collaboration Programme Task 30. phase focused on validating aerodynamic loading wind turbine rotor undergoing large motion caused by floating support structure. Numerical models Technical University Denmark 10 MW reference were validated using measurement data from 1:75 scale test performed during UNsteady Aerodynamics for FLOating (UNAFLOW) project follow-on experimental campaign, both at Politecnico di Milano tunnel. Validation was comparing loads steady (fixed platform) unsteady (harmonic conditions. For conditions, platform forced to oscillate in surge pitch directions several frequencies amplitudes. These oscillations result variation that impacts (e.g., thrust torque). conditions studied these tests, system response almost steady. Only small hysteresis airfoil performance angle attack variations attached flow observed. During experiments, speed blade held constant. However, real operating would and/or actuations, depending controller region is operating. Additional simulations control parameters conducted verify fidelity different models. Participant results showed, general, good agreement measurements need account dynamic inflow when there are changes due or actuations motion. not accounting effects predicted 9 % lower amplitude 18 higher actuations.