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  • Wind tunnel experiments and model predictions of the performance of a floating offshore wind turbine undergoing pitch motion

This content will become publicly available on December 6, 2026

Title: Wind tunnel experiments and model predictions of the performance of a floating offshore wind turbine undergoing pitch motion
Floating offshore wind turbines (FOWTs) experience multiple degree-of-freedom (DOF) motion as a result of the non-linear interactions between the aerodynamic and hydrodynamic forces exerted on the turbine rotor and the floating platform, respectively, which create complex dynamics for FOWT operations and, in turn, variability in rotor angular speed and power capture. In this work, wind tunnel experiments are performed with a down-scaled FOWT model installed on top of a robotic emulator that reproduces 4-DOF motions. Rotor rotational speed, ω, and power capture are measured for pitch motions with different amplitudes and frequencies. These experimental data are first analyzed, then used for the validation of a non-linear dynamic analytical model that predicts the variation in ω and power capture by leveraging the aerodynamic quasi-steady assumption, namely, the FOWT power curve measured under static conditions and null pitch angle is used to predict operations under dynamic conditions. The results show that good accuracy is generally achieved with the analytical model. However, dynamic aerodynamic effects occur during pitch motion that can jeopardize the accuracy of the analytical model, especially with increasing ω, motion amplitude, and in correspondence with pitch angles where the inversion of the motion direction occurs. Furthermore, it is found that these dynamic aerodynamic effects can be accurately predicted through a random forest model by providing as input pitch angle, velocity, and acceleration of the incoming wind. Among the different FOWT motion parameters, the pitch angle is found to be the most influential factor for the magnitude of the dynamic aerodynamic effects.  more » « less
Award ID(s):
2046160
PAR ID:
10657559
Author(s) / Creator(s):
;
Publisher / Repository:
AIP Publishing
Date Published:
Journal Name:
Journal of Renewable and Sustainable Energy
Volume:
17
Issue:
6
ISSN:
1941-7012
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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