PSI - Issue 1

ScienceDirect Procedia Structural Integrity 1 (2016) 197–204 Available online at www.sciencedirect.com Av ilable o line at ww.sciencedire t.com ienceDirect Structural Integ ity 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 Characterization and evaluation of the mechanical behaviour of the magnesium alloy AZ31B in multiaxial fatigue in the presence of a notch H. Videira, V. Anes, M. Freitas, L. Reis* IDMEC & Dept. of Mechanical Engineering, Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisboa, Portugal Abstract The evaluation of the behaviour of the magnesium alloy AZ31B under biaxial fatigue and short crack conditions of a specimen is presented. Test specimens present a notch, done by a drilling device, to promote the initiation of the crack in this localized region. The loading path consists on axial and torsional l adings whi h are i -phase an out- f-phase with e ch other. The crack growth rate of the specimen, under the stress intensity factor range was evaluated. Furthermore, the critical plane models, that are used to evaluate the specimen without a notch, revealed to be in this case, satisfactory to predict the angle of fracture of the specimen with a notch. The strains close to the notch were determined numerically using Finite Element Analysis. For this purpose, two finite element models were built to reproduce the proportional and non-proportional loading path. Beside this, were conducted tests with a Scanning Electron Microscope (SEM) to see the morphology of the fracture surface, in the proportional loading, which presents radial marks that are not present on the non proportional loading. The loading path shows a significant influence on the behaviour of the magnesium alloy AZ31B as well as in the life of the specimen. It is also presented a methodology to calculate the life of the specimen with a notch under biaxial load path, proportional and non proportional. Satisfactory results were achieved. © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. Keywords:Multiaxial fatigue, Finite Element Analysis, notch, life of the specimen and morphology of the fracture surface. er 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.: +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.: + 351966415585. E-mail address: henriquevideira@sapo.pt; luis.g.reis@tecnico.ulisboa.pt

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.2016.02.027