Modal-Feature-Based Detection of Localized Structural Damage in Large Wind Turbine Blades

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Published Oct 2, 2026
Samin Yaser Ahmed D. Todd Griffith Nathan L. Post M. Mohamed Sajeer

Abstract

Vibration-based prognostics and health management (PHM) of large composite wind turbine blades requires damage-sensitive features that are both globally observable and spatially diagnostic for localized damage. Natural frequencies, the most commonly used vibration indicators, are global by construction and may be insensitive to localized stiffness changes in large composite structures. Higher-order mode-shape derivatives offer theoretical advantages, but they have not been systematically compared on a reference-scale composite blade under controlled damage parametrization. This dissertation develops a parametric framework that introduces localized stiffness degradation at the composite-layup level and compares natural frequencies, mode shapes, and their spatial derivatives across a structured matrix of damage cases. Preliminary results show that frequency shifts remain below 1% for most mode–case combinations involving spatially localized stiffness degradation, while curvature-based indicators provide the strongest spatial signatures only in specific mode-and-component combinations. Selected curvature signatures also remain stable under the single rated-speed rotating condition examined. The remaining program expands the damage matrix, refines the derivative-extraction step, and cross-validates the beam-level results against shell-element models. The resulting features will then be evaluated as candidate inputs for prognostic modeling.

How to Cite

Ahmed, S. Y., Griffith, D. T., Post, N. L., & Sajeer, M. M. (2026). Modal-Feature-Based Detection of Localized Structural Damage in Large Wind Turbine Blades. Annual Conference of the PHM Society, 18(1). https://doi.org/10.36001/phmconf.2026.v18i1.5118
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Keywords

Wind turbine blade, Structural health monitoring, Localized damage, Modal analysis, Mode shape curvature

References
Ahmed, S. Y., Coleman, D., Kamal, T., Wisniewski, N., Rouser, K., & Halder, A. (2025, June). Development of a wind tunnel dynamometer assembly for evaluating unmanned aircraft co-axial propeller performance. In Proceedings of the ASME Turbo Expo 2025: Turbomachinery Technical Conference and Exposition (p. V001T01A015). Memphis, Tennessee, USA: American Society of Mechanical Engineers. (Paper No. GT2025-151812) doi: 10.1115/GT2025-151812
Ahmed, S. Y., Dutta, S., & Zhao, W. (2024). Toward the strength of the future: An experimental and computational study of Kevlar-epoxy composite laminates. In 2024 Regional Student Conferences. American Institute of Aeronautics and Astronautics. doi: 10.2514/ 6.2024-85570
Berg, J. C., & Resor, B. R. (2012, August). Numerical Manufacturing And Design Tool (NuMAD v2.0) for Wind Turbine Blades: User’s Guide (Tech. Rep. No. SAND2012-7028). Albuquerque, NM, USA: Sandia National Laboratories. doi: 10.2172/1051715
Bir, G. S. (2005, November). User’s Guide to BModes (Software for Computing Rotating Beam-Coupled Modes) (Tech. Rep. No. NREL/TP-500-39133). Golden, CO, USA: National Renewable Energy Laboratory. doi: 10.2172/861489
Bortolotti, P., Tarres, H. C., Dykes, K. L., Merz, K., Sethuraman, L., Verelst, D., & Zahle, F. (2019, May). IEA Wind TCP Task 37: Systems Engineering in Wind Energy - WP2.1 Reference Wind Turbines (Tech. Rep. No. NREL/TP-5000-73492). Golden, CO, USA: National Renewable Energy Laboratory. doi: 10.2172/1529216
Ciang, C. C., Lee, J.-R., & Bang, H.-J. (2008). Structural health monitoring for a wind turbine system: a review of damage detection methods. Measurement Science and Technology, 19(12), 122001. doi: 10.1088/0957 -0233/19/12/122001
Doebling, S. W., Farrar, C. R., & Prime, M. B. (1998). A summary review of vibration-based damage identification methods. The Shock and Vibration Digest, 30(2), 91–105. doi: 10.1177/058310249803000201
Du, Y., Zhou, S., Jing, X., Peng, Y., Wu, H., & Kwok, N. (2020). Damage detection techniques for wind turbine blades: A review. Mechanical Systems and Signal Processing, 141, 106445. doi: 10.1016/j.ymssp.2019 .106445
Fan, W., & Qiao, P. (2011). Vibration-based damage identification methods: A review and comparative study. Structural Health Monitoring, 10(1), 83–111. doi: 10.1177/1475921710365419
Griffith, D. T. (2015, March). Structural health and prognostics management for offshore wind plants (final report) (Tech. Rep. No. SAND2015-2593). Albuquerque, NM, USA: Sandia National Laboratories. doi: 10.2172/ 1178301
Pandey, A. K., Biswas, M., & Samman, M. M. (1991). Damage detection from changes in curvature mode shapes. Journal of Sound and Vibration, 145(2), 321–332. doi: 10.1016/0022-460X(91)90595-B
Wang, Y., Liang, M., & Xiang, J. (2014). Damage detection method for wind turbine blades based on dynamics analysis and mode shape difference curvature information. Mechanical Systems and Signal Processing, 48(1-2), 351–367. doi: 10.1016/j.ymssp.2014.03.006
Section
Doctoral Symposium Summaries