Articles | Volume 11, issue 4
https://doi.org/10.5194/wes-11-1305-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/wes-11-1305-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
21 Apr 2026
Research article |
| 21 Apr 2026
| 21 Apr 2026
Enhanced approach to match damage-equivalent loads in rotor blade fatigue testing
David Melcher
Department of Rotor Blades, Fraunhofer IWES, Fraunhofer Institute for Wind Energy Systems, Am Seedeich 45, 27572 Bremerhaven, Germany
Department of Wind and Energy Systems, Technical University of Denmark, Risø Campus, 4000 Roskilde, Denmark
Peter Berring
Department of Wind and Energy Systems, Technical University of Denmark, Risø Campus, 4000 Roskilde, Denmark
Kim Branner
Department of Wind and Energy Systems, Technical University of Denmark, Risø Campus, 4000 Roskilde, Denmark
Enno Petersen
CORRESPONDING AUTHOR
Department of Rotor Blades, Fraunhofer IWES, Fraunhofer Institute for Wind Energy Systems, Am Seedeich 45, 27572 Bremerhaven, Germany
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Short summary
This study shows that conventional methods in rotor blade fatigue testing can lead to substantial under-testing across major blade areas because material fatigue behavior is not well represented. An improved approach, based on strain-proportional loads with mean load correction, is proposed to define loads that produce sufficient fatigue damage across all blade areas. The results suggest that this can require up to 16 % higher uniaxial fatigue test loads than needed by conventional methods.
This study shows that conventional methods in rotor blade fatigue testing can lead to...
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