PSI - Issue 77

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ScienceDirect

Procedia Structural Integrity 77 (2026) 221–228 Structural Integrity Procedia 00 (2026) 000–000 Structural Integrity Procedia 00 (2026) 000–000

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© 2026 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ICSI organizers © 2026 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of ICSI organizers. Keywords: Continuum damage mechanics; Finite element analysis; Raindroplet impact; Polyurethane coating; Leading edge erosion Abstract Leading edge erosion of polyurethane (PU) coatings, driven by repeated high-speed raindroplet impacts, is a critical issue that limits the operational longevity of wind turbine blades. To investigate the degradation behavior of PU coatings, this study employs a numerical model integrating continuum damage mechanics (CDM) with finite element analysis. The model is specifically devel oped to track the progression of micro-scale damage in PU coatings subjected to cyclic, high-speed raindroplet impact pressures. Results demonstrate that the transient pressure from raindroplet impacts is the primary driver of degradation, creating localized high-stress regions that rapidly accelerate damage accumulation at subsurface levels. With repetitive impacts, this localized damage propagates downward and upward from the impact zone, reaching the surface. The analysis confirms a direct correlation between peak damage and maximum impact pressure, quantifying the cumulative e ff ect of repeated raindroplet strikes on coating. © 2026 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of ICSI organizers. Keywords: Continuum damage mechanics; Finite element analysis; Raindroplet impact; Polyurethane coating; Leading edge erosion International Conference on Structural Integrity Continuum damage model for the polyurethane coating of wind turbine blades Alireza Shadmani a, , Dieter Fauconnier a,b , Wim De Waele a,b a Faculty of Engineering and Architecture, Department of Electromechanical, Systems, and Metal Engineering, Soete Laboratory, Technologiepark-Zwijnaarde 46, 9052 Ghent, Belgium b Flanders Make, MIRO Lab, Ghent, Belgium Abstract Leading edge erosion of polyurethane (PU) coatings, driven by repeated high-speed raindroplet impacts, is a critical issue that limits the operational longevity of wind turbine blades. To investigate the degradation behavior of PU coatings, this study employs a numerical model integrating continuum damage mechanics (CDM) with finite element analysis. The model is specifically devel oped to track the progression of micro-scale damage in PU coatings subjected to cyclic, high-speed raindroplet impact pressures. Results demonstrate that the transient pressure from raindroplet impacts is the primary driver of degradation, creating localized high-stress regions that rapidly accelerate damage accumulation at subsurface levels. With repetitive impacts, this localized damage propagates downward and upward from the impact zone, reaching the surface. The analysis confirms a direct correlation between peak damage and maximum impact pressure, quantifying the cumulative e ff ect of repeated raindroplet strikes on coating. International Conference on Structural Integrity Continuum damage model for the polyurethane coating of wind turbine blades Alireza Shadmani a, , Dieter Fauconnier a,b , Wim De Waele a,b a Faculty of Engineering and Architecture, Department of Electromechanical, Systems, and Metal Engineering, Soete Laboratory, Technologiepark-Zwijnaarde 46, 9052 Ghent, Belgium b Flanders Make, MIRO Lab, Ghent, Belgium

1. Introduction 1. Introduction

The global transition towards renewable energy sources has positioned wind power as a cornerstone of sustainable electricity generation. The e ffi ciency and reliability of wind turbines are paramount to maximizing their energy output and economic viability. However, the operational integrity of these structures is constantly challenged by environ mental factors. A particularly critical issue is the erosion of the leading edge of wind turbine blades, caused by the repeated impact of rain droplets, hail, and other airborne particulates at high rotational speeds (Nirmal et al. (2025); Mishnaevsky et al. (2023)). This degradation can lead to a significant reduction in annual energy production (AEP), increases maintenance costs, and ultimately shortens the operational lifespan of the turbine, posing a substantial chal lenge to the wind energy industry (Ozcakmak et al. (2024)). The global transition towards renewable energy sources has positioned wind power as a cornerstone of sustainable electricity generation. The e ffi ciency and reliability of wind turbines are paramount to maximizing their energy output and economic viability. However, the operational integrity of these structures is constantly challenged by environ mental factors. A particularly critical issue is the erosion of the leading edge of wind turbine blades, caused by the repeated impact of rain droplets, hail, and other airborne particulates at high rotational speeds (Nirmal et al. (2025); Mishnaevsky et al. (2023)). This degradation can lead to a significant reduction in annual energy production (AEP), increases maintenance costs, and ultimately shortens the operational lifespan of the turbine, posing a substantial chal lenge to the wind energy industry (Ozcakmak et al. (2024)).

E-mail address: alireza.shadmani@ugent.be E-mail address: alireza.shadmani@ugent.be

2452-3216 © 2026 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ICSI organizers 10.1016/j.prostr.2026.01.030 2210-7843 © 2026 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of ICSI organizers. 2210-7843 © 2026 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of ICSI organizers.