PSI - Issue 7

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ScienceDirect Available online at www.sciencedirect.com Av ilable o line at ww.sciencedire t.com ScienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structu al Integrity 7 (2017) 182–189 Structural Integrity Procedia 00 (2017) 000–000 Available online at www.sciencedirect.com Structural Integrity Procedia 00 (2017) 000–000

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2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. ∗ Corresponding author. Tel.: + 39-010-655-8238. E-mail address: erica.vacchieri@ansaldoenergia.com 2210-7843 c 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of the 3rd International Symposium on Fatigue Design and Material Defects. The life prediction of the gas turbine (GT) critical components is very important for the OEM as it a ff ects the applied strategy for the plant maintenance plan. Moreover, the flexible operating profiles that are requested by the energy market due to the use of renewable energy resources or to the oscillating electricity price worsen the operating conditions of GT blades and vanes. In this perspective, the life prediction methodology has to be improved in order to ∗ Corresponding author. Tel.: + 39-010-655-8238. E-mail address: erica.vacchieri@ansaldoenergia.com 2210-7843 c 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of the 3rd International Symposium on Fatigue Design and Material Defects. * Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt 2452-3216 Copyright  2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of the 3rd International Symposium on Fatigue Design and Material Defects. 10.1016/j.prostr.2017.11.076 The life prediction of the gas turbine (GT) critical components is very important for the OEM as it a ff ects the applied strategy for the plant maintenance plan. Moreover, the flexible operating profiles that are requested by the energy market due to the use of renewable energy resources or to the oscillating electricity price worsen the operating conditions of GT blades and vanes. In this perspective, the life prediction methodology has to be improved in order to 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. Copyright © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility f the Scientific Committee of the 3rd International Symposium on Fatigue Design and Material Defects. Safe life approach considering creep-fatigue interaction and Weibull statistics for crack gr wth evaluation based on field feedback applied to a GT first stage blade E. Vacchieri a, ∗ , B.G. Gallo a , P. Guarnone a , E. Poggio a , P. Villari a , S.R. Holdsworth b a Ansaldo Energia S.p.A., Via N. Lorenzi 8, Genoa 16152, Italy b EMPA, U¨ berlandstrasse 129, Du¨bendorf 8600, Switzerland Abstract The increased flexibility that the energy market requires makes the service condition of gas turbine (GT) components more and more critical in terms of creep-fatigue interaction. A new lifing strategy has been developed in order to evaluate the expected life of blades and vanes in this demanding service condition taking into consideration creep-fatigue interaction. The developed lifing methodology has been applied to the first stage blade of an Ansaldo Energia F-class GT and the life map has been compared with the available field feedback. With this procedure crack initiation in the base material is considered as the lifing criteria. So, the critical locations have been correctly identified and the number of predicted cycles correspond to service experience. The available field feedback has been treated by using Weibull statistics. The statistical treatment of crack size for the critical locations provides a crack initiation evaluation that is in good agreement with the lifing strategy. Moreover, the available field feedback on the first stage blade allows the correlation of the linear crack size with its depth. This relationship has been used to define the maximum allowabl crack length for safe operation of this component. c 2017 The Authors. Published by Elsevier B.V. Peer-review under r sponsibility of the Scientific C mmittee of the 3rd Internatio al Symposium on Fatigue Des gn and Material D fects. Keywords: creep-fatigue interaction; Weibull statistic; Ni based superalloy; field feedback; crack growth; 3rd International Symposium on Fatigue Design and Material Defects, FDMD 2017, 19-22 September 2017, Lecco, Italy Safe life approach considering creep-fatigue interaction and Weibull statistics for crack growth evaluation based on field feedback applied to a GT first stage blade E. Vacchieri a, ∗ , B.G. Gallo a , P. Guarnone a , E. Poggi a , P. Villari a , S.R. Holdsworth b a Ansaldo Energia S.p.A., Via N. Lorenzi 8, Genoa 16152, Italy b EMPA, U¨ berlandstrasse 129, Du¨bendorf 8600, Switzerland Abstract The increased flexibility that the energy market requires makes the service condition of gas turbine (GT) components more and more critical in terms of creep-fatigue interaction. A new lifing strategy has been developed in order to evaluate the expected life of blades and vanes in this demanding service condition taking into consideration creep-fatigue interaction. The developed lifing methodology has been applied to the first stage blade of an Ansaldo Energia F-class GT and the life map has been compared with the available field feedback. With this procedure crack initiation in the base material is considered as the lifing criteria. So, the critical locations have been correctly identified and the number of predicted ycles correspond to service experience. The available field feedback has been treated by using Weibull statistics. The statistical treatment of crack size for the critical locations provides a crack initiation evaluation that is in good agreement with the lifing strategy. Moreover, the available field feedback on the first stage blade allows the correlation of the linear crack size with its depth. This relationship has been used to define the maximum allowable crack length for safe operation of this component. c 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of the 3rd International Symposium on Fatigue Design and Material D fects. Keywords: creep-fatigue interaction; Weibull statistic; Ni based superalloy; field feedback; crack growth; 3rd International Symposium on Fatigue Design and Material Defects, FDMD 2017, 19-22 September 2017, Lecco, Italy © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. Keywords: High Pressure Turbine Blade; Creep; Finite Element Method; 3D Model; Simulation. 1. Introduction 1. Introduction