Open AccessCross-comparative analysis of loads and power of pitching floating offshore wind turbine rotors using frequency-domain Navier-Stokes CFD and blade element momentum theory
Author(s) -
Andrea Ortolani,
Giacomo Persico,
Jernej Drofelnik,
Adrian Jackson,
M. Sergio Campobasso
Publication year - 2020
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1618/5/052016
Subject(s) - blade element momentum theory , turbine , stall (fluid mechanics) , thrust , blade pitch , blade element theory , aerodynamics , aeroelasticity , offshore wind power , rotor (electric) , computational fluid dynamics , marine engineering , frequency domain , structural engineering , wind power , turbine blade , engineering , aerospace engineering , mechanical engineering , computer science , electrical engineering , computer vision
Reliable predictions of the aero-and hydrodynamic loads acting on floating offshore wind turbines are paramount for assessing fatigue life, designing load and power control systems, and ensuring the overall system stability at all operating conditions. However, significant uncertainty affecting both predictions still exists. This study presents a cross-comparative analysis of the predictions of the aerodynamic loads and power of floating wind turbine rotors using a validated frequency-domain Navier-Stokes Computational Fluid Dynamics solver, and a state-of-the-art Blade Element Momentum theory code. The considered test case is the National Renewable Energy Laboratory 5 MW turbine, assumed to be mounted on a semi-submersible platform. The rotor load and power response at different pitching regimes is assessed and compared using both the high-and low-fidelity methods. The overall qualitative agreement of the two prediction sets is found to be excellent in all cases. At a quantitative level, the high-and low-fidelity predictions of both the mean rotor thrust and the blade out-of-plane bending moments differ by about 1 percent, whereas those of the mean rotor power differ by about 6 percent. Part of these differences at high pitching amplitude appear to depend on differences in dynamic stall predictions of the approaches.