PSI - Issue 35

ScienceDirect Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000–000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000–000 Available online at www.sciencedirect.com

www.elsevier.com/locate/procedia www.elsevier.com/locate/procedia

Procedia Structural Integrity 35 (2022) 106–114

© 2021 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 IWPDF 2021 Chair, Tuncay Yalçinkaya Abstract Slewing bearings in wind turbines are meant to last 20 years or longer. But wind turbine accidents (structural failure) occur nevertheless in some cases earlier. Minimizing the risk and with this enhancing the public acceptance of wind turbines is of great importance for the increase of alternative energy production. For a more accurate prediction of the service life of slewing bearings XFEM calculations with crack initiation and crack propagation are developed using Abaqus XFEM. The material parameters such as Paris coefficients for crack propagation and fracture toughness values (K IC ) were measured in advance on samples of different heat treatment conditions. With a linear elastic fracture mechanics approach the local stress intensity factor range ∆ K for a given starting crack front is calculated. Coupling this information with the Paris-law and a maximum crack propagation interval of 0.1 0.3 mm, the number of cycles to failure during crack propagation is determined. The crack is extended stepwise until ∆ K reaches the limiting fracture toughness of the material. The crack propagation model was first validated on different test specimen geometries. Correlating these first simulated test results with experimental data the crack initiation phase can be estimated. The simulation of real components, such as bearings, will be developed subsequently, using calculated stress distributions provided by other partners in the project as input parameters (sub-structure approach). Fatigue tests are also done on pre-corroded specimens since bearing failure may also be promoted by an unfavorable combination of overloads and corrosion damage. © 2021 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 IWPDF 2021 Chair, Tuncay Yalçinkaya Keywords: Slewing bearing; material properties; simulation; crack propagation; prediction of service life 2nd International Workshop on Plasticity, Damage and Fracture of Engineering Materials Crack propagation modelling for service life prediction of large slewing bearings Vera Friederici a * , Jens Schumacher a , Brigitte . Clausen b a Leibniz Institute for Materials Engineering – IWT, Badgasteiner Str. 3, 28359 Bremen, Germany b University of Bremen, Faculty of Production Engineering, Research Group Materials Engineering Metals, Badgasteiner Str. 1, 28359 Bremen, Germany Abstract Slewing bearings in wind turbines are meant to last 20 years or longer. But wind turbine accidents (structural failure) occur nevertheless i some cases ea lier. Mini izi g he risk and with this enhancing the public acceptance of wind turbines is of great importance for the increase of alternative ener y production. For a more ccurate predict on of the service l fe of slewing bearings XFEM calculations with crack initiation and crack propagation are dev loped using Abaqus XFEM. The mat rial parameters such as Paris coeffic e ts for crack prop gation and fracture tough ess valu s (K IC ) were meas red in advance on sam les of different heat t eatment co diti ns. With a linear elastic fr t r mec anics pproach the local stress intensity fa tor range ∆ K for a given star ing crack fr t s calculated. Coupling this information with the Paris-law and a maximum crack propag tion interval of 0.1 0.3 mm, the number of cycles to fail re during crack propagation is determined. The cr ck is extended stepwise until ∆ K reaches the li iting fracture toughness of th material. The crack propagation model was first validated on differ nt test specim n geometries. Correlating thes first simulated test results with ex erimental data the crack initiation phase can be estimat d. The simula ion of real compon nts, such as bearings, will be developed subsequently, using alculated stress distribution provi ed by other part ers in the project as input parameters (sub-structure approach). Fatigue tests re also on on pre-corr ded specimens since bearing failur may also be romoted by an unfavorable combination of overload nd corrosion damage. © 2021 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 u der re ponsibility of IWPDF 2021 Chair, Tuncay Yalçinkay Keywords: Slewing bearing; material properties; simulation; crack propagation; prediction of service life 2nd International Workshop on Plasticity, Damage and Fracture of Engineering Materials Crack propagation modelling for service life prediction of large slewing bearings Vera Friederici a * , Jens Schumacher a , Brigitte . Clausen b a Leibniz Institute for Materials Engineering – IWT, Badgasteiner Str. 3, 28359 Bremen, Germany b University of Bremen, Faculty of Production Engineering, Research Group Materials Engineering Metals, Badgasteiner Str. 1, 28359 Bremen, Germany

* Corresponding author. Tel.: +49-421-218-51427; fax: +49-421-218-51333. E-mail address: friederici@iwt-bremen.de * Corresponding author. Tel.: +49-421-218-51427; fax: +49-421-218-51333. E-mail address: friederici@iwt-bremen.de

2452-3216 © 2021 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 IWPDF 2021 Chair, Tuncay Yalçinkaya 2452-3216 © 2021 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 IWPDF 2021 hair, Tuncay Yalçinkaya

2452-3216 © 2021 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 IWPDF 2021 Chair, Tuncay Yal ç inkaya 10.1016/j.prostr.2021.12.054