PSI - Issue 2_B

ScienceDirect Available online at www.sciencedirect.com Av ilable online at ww.sciencedire t.com Sci ceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Struc ural Integrity 2 (2016) 2432–2438 Sci nceDirect Structural Integrity Procedia 00 (2016) 000–000 ScienceDirect Structural Integrity Procedia 00 (2016) 000–000 Available online at www.sciencedirect.com Available online at www.sciencedirect.com

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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. 21st European Conference on Fracture, ECF21, 20-24 June 2016, Catania, Italy Irwin's plastic zone size assessment for interacting cracks in a circular plane subjected to anti-plane deformation Hossein Teimoori a , Reza Teymoori Faal b, * a Department of Mathematics and Computer Science, Allameh Tabatabai University, Tehran, Iran b Faculty of Engineering, University of Zanjan, P.O. Box 45195-313, Zanjan, Iran The solution of screw dislocatio i an isotropic elastic circular plane is obtained using the image method. The solution is used to derive integral equations for a cracked circular plane under self-equilibrating anti-plane loadings. Based on the small-scale yielding the solution of these equations, are utilized to determine stress components around a crack tip. Employing Irwin's model the length of the plastic zone in front of the crack is determined. Also using the von Mises yield criterion the stress components are utilized to define the boundary of plastic region around a crack tip. © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21. Keywords: Irwin's model; Anti-plane defor ation; Crack tip plastic region; Dislocation density; Small-scal yielding 1. Introduction Forming of plastic region at a crack tip even under small applied loads is a remarkable subject. Particularly for cracked metallic structures, the size of the plastic region at a crack tip is of greatest importance. Some explanations on the significance of this subject can be found in the reference (Hassani et al., 2015) and a few related papers have been reviewed there. First, using the distributed dislocation technique, Hassani et al. (2015) determined the stress components around a crack tip which was located in an isotropic layer. U der the hypotheses of linear fracture mechanics, they used these components to define the boundary of the plastic region employing von Mises yield 21st European Conference on Fracture, ECF21, 20-24 June 2016, Catania, Italy Irwin's plastic zone size assessment for interacting cracks in a circular plane subjected to anti-plane deformation Hossein Teimoori a , Reza Teymoori Faal b, * a Department of Mathematics and Computer Science, Allameh Tabatabai University, Tehran, Iran b Faculty of Engineering, University of Zanjan, P.O. Box 45195-313, Zanjan, Iran Abstract The solution of screw dislocation in an isotropic elastic circular plane is obtained using the image method. The solution is sed to de ive integr l equatio s f r a crack d ir ular plan under self- quilibrating anti-plan loadings. Based on the small-scal yielding the solution of these quations, are utilize to det rm ne stress com onents round a crack tip. Employing Irw n's model the length of th plastic zone in front of he crack s de rmined. Also using the von Mises yield criterion the stress compo ents are utilized to d f e the b undary of plastic region around a crack tip. © 2016 The Authors. Published by Elsevier B.V. Peer-review under respons bility of the Scientific Committee of ECF21. Keywords: Irwin's model; Anti-plane deformation; Crack tip plastic region; Dislocation density; Small-scale yielding 1. Introduction Forming of plastic region at a crack tip even under small applied loads is a remarkable subject. Particularly for cracked metallic structures, the size of the plastic region at a crack tip is of great st importance. Some explanations on th significance of this subject can be found n the referen e (Hassani et al., 2015) and a few relat d papers have been reviewed th re. Fir t, using the distributed dislocation technique, Hassani et al. (2015) det rmined the stress components around a c ack t p w ich was located in n isotropic layer. Under he hypothes s of linear fracture mecha ic , they u ed these components to defin the boundary of the plastic egion employing von Mises yield 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. © 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. Abstract

* 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 ECF21. 2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under r sponsibility of the Scientific Committee of ECF21. * Corresponding author. Tel.: +98 241 515 2600; fax: +98 241 515 2762. E-mail address: faal92@yahoo.com * Corresponding author. Tel.: +98 241 515 2600; fax: +98 241 515 2762. E-mail address: faal92@yahoo.com

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.2016.06.304