PSI - Issue 57

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ScienceDirect

Procedia Structural Integrity 57 (2024) 169–178 Structural Integrity Procedia 00 (2023) 000–000 Structural Integrity Procedia 00 (2023) 000–000

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© 2024 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 the scientific committee of the Fatigue Design 2023 organizers © 2023 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 the scientific committee of the Fatigue Design 2023 organizers. Keywords: Wind turbine rotor blade; debonding, adhesive joint; Virtual Crack Close Technique; FEM; FEA; Abaqus; The numerical predictions as well as the manufactured and instrumented blade sets the framework to subsequently execute experimental tests of damage growth in the adhesive joint of the bondline in order to compare numerical and experimental data. The experimental demonstration will allow to better understand the complexity of damage growth of composite structures under fatigue loading and the necessity of accurate numerical prediction tools for reliable prognostic health management systems. © 2023 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 the scientific committee of the Fatigue Design 2023 organizers. Keywords: Wind turbine rotor blade; debonding, adhesive joint; Virtual Crack Close Technique; FEM; FEA; Abaqus; Fatigue Design 2023 (FatDes 2023) SparCap / Shear Web Debonding Under Fatigue Loading Studied On The DTU 12.6m Wind Turbine Blade Philipp Ulrich Haselbach a, ∗ , Peter Berring a a Technical University of Denmark, DTU Wind and Energy Systems, Frederiksborgvej 399, Roskilde DK-4000, Denmark Abstract Understanding fatigue damage initiation and propagation of composite wind turbine blades is an essential step towards the design of reliable prognostic and health management systems (PHM) and to improve lifetime predictions. This study presents a numerical investigation of the debonding process in the spar cap / shear web region of a full-scale composite wind turbine blade under fatigue loading and presents the manufacturing approach for creating initial debondings. For this purpose, numerical simulations have been performed to design and specify the size and locations of artificial defects to provoke steady, controllable damage growth in the adhesive bondline between the rear shear web and cap region of the DTU 12.6m wind turbine blade under fatigue loading. Subsequently, these artificial defects are embedded into the manufacturing process of the composite wind turbine blade with the help of slip foils and partially perforated slip foils to create regions with no bonding, 30% and 50% bonding of the contact surfaces of the adhesive joint, respectively. The numerical predictions as well as the manufactured and instrumented blade sets the framework to subsequently execute experimental tests of damage growth in the adhesive joint of the bondline in order to compare numerical and experimental data. The experimental demonstration will allow to better understand the complexity of damage growth of composite structures under fatigue loading and the necessity of accurate numerical prediction tools for reliable prognostic health management systems. Fatigue Design 2023 (FatDes 2023) SparCap / Shear Web Debonding Under Fatigue Loading Studied On The DTU 12.6m Wind Turbine Blade Philipp Ulrich Haselbach a, ∗ , Peter Berring a a Technical University of Denmark, DTU Wind and Energy Systems, Frederiksborgvej 399, Roskilde DK-4000, Denmark Abstract Understanding fatigue damage initiation and propagation of composite wind turbine blades is an essential step towards the design of reliable prognostic and health management systems (PHM) and to improve lifetime predictions. This study presents a numerical investigation of the debonding process in the spar cap / shear web region of a full-scale composite wind turbine blade under fatigue loading and presents the manufacturing approach for creating initial debondings. For this purpose, numerical simulations have been performed to design and specify the size and locations of artificial defects to provoke steady, controllable damage growth in the adhesive bondline between the rear shear web and cap region of the DTU 12.6m wind turbine blade under fatigue loading. Subsequently, these artificial defects are embedded into the manufacturing process of the composite wind turbine blade with the help of slip foils and partially perforated slip foils to create regions with no bonding, 30% and 50% bonding of the contact surfaces of the adhesive joint, respectively.

1. Introduction 1. Introduction

Wind turbine rotor blades are usually designed for a lifetime of 25 years. During the lifetime, wind turbine rotor blades experience are variety of dynamic loads. In order to ensure the structural integrity of the rotor blade, shear webs connect in the interior of the blade the upper and lower spar cap regions of the aerodynamic shells. These spars / shear web connections carry the shear load and part of the bending loads by restraining the cross section against transverse Wind turbine rotor blades are usually designed for a lifetime of 25 years. During the lifetime, wind turbine rotor blades experience are variety of dynamic loads. In order to ensure the structural integrity of the rotor blade, shear webs connect in the interior of the blade the upper and lower spar cap regions of the aerodynamic shells. These spars / shear web connections carry the shear load and part of the bending loads by restraining the cross section against transverse

∗ Corresponding author. Tel.: + 45 50156403 E-mail address: phih@dtu.dk ∗ Corresponding author. Tel.: + 45 50156403 E-mail address: phih@dtu.dk

2452-3216 © 2024 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 the scientific committee of the Fatigue Design 2023 organizers 10.1016/j.prostr.2024.03.020 2210-7843 © 2023 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 the scientific committee of the Fatigue Design 2023 organizers. 2210-7843 © 2023 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 the scientific committee of the Fatigue Design 2023 organizers.