PSI - Issue 5

ScienceDirect Available online at www.sciencedirect.com Av ilable o line at ww.sciencedire t.com ienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structu al Integrity 5 (2017) 951–958 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2017) 000 – 000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2017) 000 – 000

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

www.elsevier.com/locate/procedia

XV Portuguese Conference on Fracture, PCF 2016, 10-12 February 2016, Paço de Arcos, Portugal Thermo-mechanical modeling of a high pressure turbine blade of an airplane gas turbine engine P. Brandão a , V. Infante b , A.M. Deus c * a Department of Mechanical Engineering, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1, 1049-001 Lisboa, Portugal b IDMEC, Department of Mechanical Engineering, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1, 1049-001 Lisboa, Portugal c CeFEMA, Department of Mechanical Engineering, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1, 1049-001 Lisboa, Portugal Abstract During their operation, modern aircraft engine components are subjected to increasingly demanding operating conditions, especially the high pressure turbine (HPT) blades. Such conditions cause these parts to undergo different types of time-dependent degradation, one of which is creep. A model using the finite element method (FEM) was developed, in order to be able to predict the creep behaviour of HPT blades. Flight data records (FDR) for a specific aircraft, provided by a commercial aviation company, were used to obtain thermal and mechanical data for three different flight cycles. In order to create the 3D model needed for the FEM analysis, a HPT blade scrap was scanned, and its chemical composition and material properties were obtained. The data that was gathered was fed into the FEM model and different simulations were run, first with a simplified 3D rectangular block shape, in order to better establish the model, and then with the real 3D mesh obtained from the blade scrap. The overall expected behaviour in terms of displacement was observed, in particular at the trailing edge of the blade. Therefore such a model can be useful in the goal of predicting turbine blade life, given a set of FDR data. 2nd International Conference on Structural Integrity, ICSI 2017, 4-7 September 2017, Funchal, Madeira, Portugal Analysis of the design of experiments of offshore wind turbine fatigue reliability design with Kriging surfaces Rui Teixeira a* , Alan O’Connor a , Maria Nogal a , Nandakumar Krishnan b , James Nichols b a Trinity College Dublin, College Green, Dublin 2, Ireland b Lloyd’s Register, 71 Fenchurch Street, London, United Kingdom Abstract The fatigue design of Offshore Wind Turbines (OWT) is one of the most resource demanding tasks in the OWT design process. Techniques have been developed recently to simplify the amount of effort needed to design to structural fatigue. This is the example of the usage of Kriging surrogate models. These may be used in OWTs design not only, to reduce the computational effort needed to analyse an OWT, but also to allow their design to be robust. Due to the stress variability and its non-linear character, the short-term fatigue damage variability is high, and converging the stochastic field approached by the surrogate model in relation to the real observations is challenging. A thorough analysis of the different components that load an OWT and are more critical for the tower component fatigue life is required, and therefore, presented and discussed in the current paper. The tower, jointly with the foundation, are particular components of the OWT regarding the fatigue analysis process. Statistical assessments of the extrapolation of fatigue loads for the tower and the influence of the environmental parameters in the short-term damage are presented in this paper. This sets a support analysis for the creation of the Kriging response surfaces for fatigue analysis. NREL’s 5MW monopile turbine is used due to its state of the art character. Five environmental variables are considered in the analysis. A sensitivity analysis is conducted to identify which variables are most prominent in the quantification of the short-term damage uncertainty in the tower. The decoupling of the different external contributions for the fatigue life is a major contribution of the work presented. Preliminary guidelines are drawn for the creation of surrogate models to analyse fatigue of OWT towers and the most relevant conclusions ar pres nted in an industry-oriented design outline regarding the most critical random variables that influence OWT short-term fatigue calculation. 2nd International Conference on Structural Integrity, ICSI 2017, 4-7 September 2017, Funchal, Madeira, Portugal Analysi of the d sign of xperiments of offshore wind turbine fatigue reliability design with Kriging surfaces Rui Teixeira a* , Alan O’Connor a , Maria Nogal a , Nandakumar Krishnan b , James Nichols b a Trinity College Dublin, College Green, Dublin 2, Ireland b Lloyd’s Register, 71 Fenchurch Street, London, United Kingdom Abstract he fatigue design of Offsh r Wind Turbines (OWT) is one of th most r source demanding tasks in the OWT de ign process. Tec niques have bee devel ped recent y to simplif th amou t of effort needed to design to structural fatig e. This is the example of the u age of Kriging surr gate models. These may be used in OWTs design not only, to reduce the computational effort needed to analyse an OWT, but also to allow their d sign to be robust. Due to the stress variability and its n n-linear character, the short-t rm fatigue damage variab lity is high, and converging the stochastic field approached by th surr gate model in rel tio to the real observations s challenging. A thorough analysis of th diff rent components that load a OWT and are more critical for the tower component fatigue life is required, and therefore, presente and discussed in the curre t paper. The tower, jointly wi h the foundati n, are particular c mponents of th OWT r garding the atigue analysis process. Statis ical assessments of th extrapolation of fatigue loads for the tower and the influ nce of the envi onmental parameters in the short-term damage are presented in this paper. Thi sets a supp rt analysis for the cre tion of the Kriging response surfac for fatigue analysis. NREL’s 5MW monopile turbine is used due to its state of t e rt char cter. Five environmental v riables are considered in the analysis. A s ns tivity analysis is conducted to identify wh ch variables are most prominent in the quantif cat on of the short-term damag uncertainty in the tower. The decoupling of the different external cont ibutions for the fatigue life is a maj r contributio of the work prese ted. Prel min ry guid lines are drawn for the cre tion of surrogate models to analy e fatigue of OWT towers and he most r levant conclusions are presented n an industry-oriented design outline regarding the most critical random variables at infl ence OWT short-term fatigue calculation. © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. © 2017 Th A thors. Published b Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ICSI 2017. © 2017 The Autho s. Publ shed by Elsevier B.V. Peer-review under re ponsibility of the Sci ntific Com it ee of ICSI 2017. © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ICSI 2017 Keywords: High Pressure Turbine Blade; Creep; Finite Element Method; 3D Model; Simulation.

Keywords: Offshore wind turbine; Reliability; Kriging surrogate model; Sensitivity anaysis; Short-term fatigue damage; Keywords: Offshore wind turbine; Reliability; Kriging surrogate model; Sensitivity anaysis; Short-term fatigue damage;

* Corresponding author. Tel.: +353 1 896 1000; E-mail address: rteixeir@tcd.ie * Corresponding author. Tel.: +353 1 896 1000; E-mail address: rteixeir@tcd.ie

2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. 2452-3216  2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ICSI 2017 10.1016/j.prostr.2017.07.132 * Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt 2452 3216 © 2017 Th Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ICSI 2017. 2452-3216 © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ICSI 2017.