PSI - Issue 2_A

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 Struc ural Integrity 2 (2016) 1351–1358 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2016) 000–000

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. 21st European Conference on Fracture, ECF21, 20-24 June 2016, Catania, Italy Defect sensitivity of single-crystal nano-sized Cu beams Solveig Melin*, Per Hansson, Aylin Ahadi Division of Mechanics, Lund University,P.O. Box 118, 22100 Lund, Sweden Abstract Molecular dynamics simulations of nano-sized beams with square cross sections of single-crystal Cu, solid as well as holding defects and loaded in displacement controlled tension until rupture have been performed. The defects are either edge crack-lik or through-the-thickness voids. Three different cross section sizes and two different crystallographic orientations have been investigated. As expected, both geometry and crystal orientation influence the mechanical behavior. The strain at plastic initiation was, however, found almost independent of cross section size at given geometry and crystal orientation. Not surprisingly, the presence of defects lowers the strain at both plastic initiation and at rupture. More surprising is that embedded through-the-thickness voids under some circumstances might close to heal the beam cross section. The healing process seems to strengthen the beam and delay the final rupture. This applies for thin enough beams, allowing strong enough interatomic forces over the void, assisted by pertinent slip events. © 2016 S Melin, P Hansson, A Ahadi. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21. Keywords: Defect nano-beams, single-crystal Cu, void closure in nano-beams, tensile nano-beams 1. Introduction Nano-siz d components are contained in a wide verity of everyday products; medical as well as functional applications are today commonly found on the arket. Since it is well known that the mechanical properties of engineering materials at the nano-scale differ from corresponding macroscopic ones, a new awareness of the necessity of revising traditional dimensioning concepts, established for structures at the macro-scale, is emerging in the engineering community. A size effect is obviously at hand, cf. eg. Ahadi and Melin (2016) and Olsson et al. (2007). d u Copyright © 2016 The Aut ors. Published by Elsevier B.V. This s an op n access article under the CC BY-NC-ND licens (ht p:// ativecommons.org/licenses/by-nc-nd/4.0/). Peer-review und r responsibility of the Scientific Committee of ECF21. © 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.: +46 46 223037. E-mail address: solveig.melin@mek.lth.se

* Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt 2452-3216 © 2016 S Melin, P Hansson, A Ahadi. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21.

2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. Copyright © 2016 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 ECF21. 10.1016/j.prostr.2016.06.172