Experimental Study on Influence of Pitch Motion on the Wake of a Floating Wind Turbine Model

Energies

Stanislav Rockel¹  Elizabeth Camp³  Jonas Schmidt²  Joachim Peinke¹  Raul Bayoán Cal³ 

[1] ForWind, University of Oldenburg, Ammerländer Heerstr. 136, 26129 Oldenburg, Germany; E-Mails:;Fraunhofer IWES, Ammerländer Heerstr. 136, 26129 Oldenburg, Germany; E-Mail:;Department of Mechanical and Materials Engineering, Portland State University, P.O. Box 751, Portland, OR 97207, USA; E-Mails:

关键词: wake;    wind tunnel;    experiment;    floating wind turbine;    stereo particle image velocimetry (PIV);    unsteady aerodynamics;    wake models;    offshore;   

DOI  :  10.3390/en7041954

来源: mdpi

【 摘 要 】

Wind tunnel experiments were performed, where the development of the wake of a model wind turbine was measured using stereo Particle Image Velocimetry to observe the influence of platform pitch motion. The wakes of a classical bottom fixed turbine and a streamwise oscillating turbine are compared. Results indicate that platform pitch creates an upward shift in all components of the flow and their fluctuations. The vertical flow created by the pitch motion as well as the reduced entrainment of kinetic energy from undisturbed flows above the turbine result in potentially higher loads and less available kinetic energy for a downwind turbine. Experimental results are compared with four wake models. The wake models employed are consistent with experimental results in describing the shapes and magnitudes of the streamwise velocity component of the wake for a fixed turbine. Inconsistencies between the model predictions and experimental results arise in the floating case particularly regarding the vertical displacement of the velocity components of the flow. Furthermore, it is found that the additional degrees of freedom of a floating wind turbine add to the complexity of the wake aerodynamics and improved wake models are needed, considering vertical flows and displacements due to pitch motion.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.