PSI - Issue 1

ScienceDirect Procedia Structural Integrity 1 (2016) 166–172 Available online at www.sciencedirect.com Av ilable o line at ww.sciencedire t.com ScienceDirect Structural Integ ity Procedia 00 (2016) 000 – 000 Available online at www.sciencedirect.com ScienceDirect StructuralIntegrity Procedia 00 (2016) 000 – 000 Available online at www.sciencedirect.com ScienceDirect StructuralIntegrity Procedia 00 (2016) 000 – 000

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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. XV Portuguese Conference on Fracture, PCF 2016, 10-12 February 2016, Paço de Arcos, Portugal Influence of node release in crack propagation simulation under variable amplitude loading Luiz C.H.Ricardo a * a Materials Technology Department, IPEN, University of São Pa lo, Brazil,Instituto de Pesquisas Energéticas e Nucleares, Av. Lineu Prestes 2242 - Cidade Universitária - São Paulo - SP BRASIL- CEP: 05508-000 Abstract The aim of this paper is to verify the effect of different crack propagation rates in determination of crack opening and closing stress of an ASTM specimen under a standard suspension spectrum loading from FD&E SAE Load Histories by finite element analysis. The crack propagation simulation was based on nodes release in the minimum loads to minimize convergence problems. To understand the crack propagation processes under variable amplitude loading, retardation effects are observed and discussed. Keywords: Fatigue, crack propagation simulation, finite Element method, retardation 1. Introduction The most common technique for predicting the fatigue life of automotive, aircraft and wind turbine structures is Miner’s rule (1945). Despite the known deviations, inaccuracies and proven conservatism of Miner’s cumulative da age law, it is even nowadays being sed in the design of many advanced structures. Fracture mechanics techniques for fatigue life predictions remain as a backup in design procedures. The most important and difficult problem in using fracture mechanic concepts in design seems to be the use of crack growth data to predict fatigue life. The experim ntally obta ned data is used to derive a relationship between stress intensity range ( Δ K) and crack growth per cycle (da/dN). XV Port guese C nferenc on Fracture, PCF 2016, 10-12 February 2016, Paço de Arcos, Po tugal Influence of node release in crack propagation simulation under variable amplitude loading Luiz C.H.Ricardo a * a Materials Technology Department, IPEN, University of São Paulo, Brazil,Instituto de Pesquisas Energéticas e Nucleares, Av. Lineu Prestes 2242 - Cidade Universitária - São Paulo - SP BRASIL- CEP: 05508-000 Abstract The aim of this paper is to verify the effect of different crack propagation rates in determination of crack opening and closing stress of an ASTM specimen under a standard suspension spectrum loading from FD&E SAE Load Histories by finite element analysis. The crack propagation simulation was based on nodes release in the minimum loads to min miz convergence problems. To understand the crack propagation processes under variable amplitude loading, retardation effects are observed and disc ssed. Keywords: Fatigue, crack propagation simulation, finite Element method, retardation 1. Introduction The most common technique for predicting the fatigue life of automotive, aircraft and wind turbine structures is Miner’s rule (1945). Despite the known deviations, inaccuracies and proven conservatism of Miner’s cumulative damage law, it is even nowadays being used in the design of many advanced structures. Fracture mechanics techniques for fatigue life predictions remain as a backup in design procedures. The most important and difficult problem in using fracture m ch nics concep s in d sign seems to b the se f crack growth data to predict fatigue life. The experimentally obtained data is used to derive a relationship between stress intensity range ( Δ K) and crack growth per cycle (da/dN). Copyright © 2015 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 PCF 2016. © 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.

* Corresponding author. Tel.: +55-11-3133-9201 fax: +55-11-3133-9018 E-mail address:lricardo@ipen.br

* Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt 2452-3216© 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. * Corresponding author. Tel.: +55-11-3133-9201 fax: +55-11-3133-9018 E-mail address:lricardo@ipen.br

2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. Copyright © 2015 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 PCF 2016. 10.1016/j.prostr.2016.02.023 2452-3216© 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016.