Blade System Design Studies Volume I: Composite Technologies for Large Wind Turbine Blades

The adoption of blunt trailing edge airfoils for the inner regions of large wind turbine blades has been proposed. Blunt trailing edge airfoils would not only provide increased structural volume, but have also been found to improve the lift characteristics of airfoils and therefore allow for section shapes with a greater maximum thickness. Limited experimental data makes it difficult for wind turbine designers to consider and conduct tradeoff studies using these section shapes. This lack of experimental data precipitated the present analysis of blunt trailing edge airfoils using computational fluid dynamics. Several computational techniques are applied including a viscous/inviscid interaction method and several Reynolds-averaged Navier-Stokes methods.

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Sustainable End-of-Life Management of Wind Turbine Blades: Overview of Current and Coming Solutions

Materials ◽

10.3390/ma14051124 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1124

Author(s):

Leon Mishnaevsky Mishnaevsky

Keyword(s):

Wind Turbine ◽

End Of Life ◽

Wind Turbines ◽

Natural Fiber ◽

Turbine Blades ◽

Wind Turbine Blades ◽

Maintenance And Repair ◽

Life Management ◽

Large Wind

Various scenarios of end-of-life management of wind turbine blades are reviewed. “Reactive” strategies, designed to deal with already available, ageing turbines, installed in the 2000s, are discussed, among them, maintenance and repair, reuse, refurbishment and recycling. The main results and challenges of “pro-active strategies”, designed to ensure recyclability of new generations of wind turbines, are discussed. Among the main directions, the wind turbine blades with thermoplastic and recyclable thermoset composite matrices, as well as wood, bamboo and natural fiber-based composites were reviewed. It is argued that repair and reuse of wind turbine blades, and extension of the blade life has currently a number of advantages over other approaches. While new recyclable materials have been tested in laboratories, or in some cases on small or medium blades, there are remaining technological challenges for their utilization in large wind turbine blades.

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Innovative design approaches for large wind turbine blades : final report.

10.2172/918296 ◽

2004 ◽

Cited By ~ 1

Author(s):

Keyword(s):

Wind Turbine ◽

Turbine Blades ◽

Final Report ◽

Wind Turbine Blades ◽

Innovative Design ◽

Large Wind

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Innovative design approaches for large wind turbine blades

Wind Energy ◽

10.1002/we.128 ◽

2005 ◽

Vol 8 (2) ◽

pp. 141-171 ◽

Cited By ~ 52

Author(s):

K. J. Jackson ◽

M. D. Zuteck ◽

C. P. van Dam ◽

K. J. Standish ◽

D. Berry

Keyword(s):

Wind Turbine ◽

Turbine Blades ◽

Wind Turbine Blades ◽

Innovative Design ◽

Large Wind

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Evaluation of dual-axis fatigue testing of large wind turbine blades

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406211428013 ◽

2011 ◽

Vol 226 (7) ◽

pp. 1693-1704 ◽

Cited By ~ 18

Author(s):

Peter R Greaves ◽

Robert G Dominy ◽

Grant L Ingram ◽

Hui Long ◽

Richard Court

Keyword(s):

Service Life ◽

Wind Turbine ◽

Fatigue Testing ◽

Turbine Blades ◽

Bending Moment ◽

Fatigue Tests ◽

Simulation Software ◽

Wind Turbine Blades ◽

Moment Distribution ◽

Large Wind

Full-scale fatigue testing is part of the certification process for large wind turbine blades. That testing is usually performed about the flapwise and edgewise axes independently but a new method for resonant fatigue testing has been developed in which the flapwise and edgewise directions are tested simultaneously, thus also allowing the interactions between the two mutually perpendicular loads to be investigated. The method has been evaluated by comparing the Palmgren–Miner damage sum around the cross-section at selected points along the blade length that results from a simulated service life, as specified in the design standards, and testing. Bending moments at each point were generated using wind turbine simulation software and the test loads were designed to cause the same amount of damage as the true service life. The mode shape of the blade was tuned by optimising the position of the excitation equipment, so that the bending moment distribution was as close as possible to the target loads. The loads were converted to strain–time histories using strength of materials approach, and fatigue analysis was performed. The results show that if the bending moment distribution is correct along the length of the blade, then dual-axis resonant testing tests the blade much more thoroughly than sequential tests in the flapwise and edgewise directions. This approach is shown to be more representative of the loading seen in service and can thus contribute to a potential reduction in the weight of wind turbine blades and the duration of fatigue tests leading to reduced cost.

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