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Servo-aero-gravo-elastic (SAGE) scaling and its application to a 13-MW downwind turbine

Journal Article · · Journal of Renewable and Sustainable Energy
DOI:https://doi.org/10.1063/5.0021171· OSTI ID:1703880

Reduced scale wind turbines can be extremely cost-effective to test new rotor concepts since prototype costs are heavily dependent on the rotor diameter. Ideally, the scaled model would have the same non-dimensional deflections, dynamics, and control behavior as the full-scale model. This would provide a high-fidelity demonstration of the full-scale performance, which is ideal if the full-scale turbine has significant aeroelastic interactions. To this end, servo-aero-gravo-elastic (SAGE) scaling is developed and applied to a 13-MW turbine that is scaled to a 20% scale model. The scaling preserves the tip-speed ratio, the rotor speed normalized by the flapping frequency, and the tip deflections normalized by the blade length. In addition, the controller employs the same control structure (gain-scheduled pitch control and variable speed torque control) and is scaled dynamically (e.g., matching non-dimensional time constant of the pitch angle, etc.). Furthermore, the thrust, gravity, and centrifugal moments are scaled such that the load angles are preserved as a function of a non-dimensional wind speed. However, the environmental scaling must consider differences in Reynolds number (since this parameter cannot be held constant) and subsequent changes in the axial induction factor. While the presented results showcase these differences during operational conditions, the non-dimensional tip deflections remain comparable through all wind speed ranges, indicating the viability of the SAGE scaling method in matching full-scale aeroelastic responses.

Sponsoring Organization:
USDOE Advanced Research Projects Agency - Energy (ARPA-E)
Grant/Contract Number:
AR0000667
OSTI ID:
1703880
Journal Information:
Journal of Renewable and Sustainable Energy, Journal Name: Journal of Renewable and Sustainable Energy Journal Issue: 6 Vol. 12; ISSN 1941-7012
Publisher:
American Institute of PhysicsCopyright Statement
Country of Publication:
United States
Language:
English

References (12)

Downwind pre-aligned rotors for extreme-scale wind turbines: Downwind pre-aligned rotors for extreme-scale wind turbines journal January 2017
Gravo‐aeroelastic scaling of a 13‐MW downwind rotor for 20% scale blades journal September 2020
Wind Turbine Control for Load Reduction journal January 2003
Evaluating Reynolds number effects in small-scale wind turbine experiments journal September 2013
Wind tunnel testing of scaled wind turbine models: Beyond aerodynamics journal April 2014
Aerodynamic design methodology for wind tunnel tests of wind turbine rotors journal August 2017
State of the art in wind turbine aerodynamics and aeroelasticity journal June 2006
Analyzing scaling effects on offshore wind turbines using CFD journal November 2015
Pre-aligned downwind rotor for a 13.2 MW wind turbine journal February 2018
Ground testing of a 1% gravo-aeroelastically scaled additively-manufactured wind turbine blade with bio-inspired structural design journal April 2020
Control of Wind Turbines journal March 2011
Definition of a 5-MW Reference Wind Turbine for Offshore System Development report February 2009

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