PSI - Issue 2_A

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 Struc ural Integrity 2 (2016) 1252–1259 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity 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. 21st European Conference on Fracture, ECF21, 20-24 June 2016, Catania, Italy Assessing osteosynthesis techniques for pelvic fractures using Digital Image Correlation M. Karanika a , D. Georgiou a , S. Darmanis b , Α . Papadogoulas b , E. D. Pasiou a , S. K. Kourkoulis a * a Laboratory of Testing and Materials, Department of Mechanics, Unit of Biomechanics, National Technical University of Athens, 157 73, Greece b NIMITS Hospital, Monis Petraki 10-12, 115 21, Athens, Greece Abstract Various techniques used in orthopedic surgery for the fixation of pelvic fractures are assessed experimentally from the biomech anical point of view. The protocol designed consisted of twenty five experiments with cadaveric semi-pelvises which were artificial ly fractured. The fractures simulated the extremely dangerous T-type ones. Five fixation techniques, comprising of simple and self locking plates with fixation screws, were assessed. For the determination of the displacement field developed three-dimensional Digital Image Correlation (3D-DIC) was used. It was indicated that 3D-DIC is advantageous against classical sensing techniques since it allows convenient selection of critical pairs of material points (both prior and after the experiments, without any limit as to their number) for the estimation of the opening of the fracture. Moreover it permits determination of the pure relative sliding bet ween the various parts of the T-fractured pelvises as it allows isolatio of rigid body displacem nt an rotation. From the clinical point of vi w it appears that combin tion of locking reconstruction plates with simple ones offers incr ased stability. © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21. Keywords: pelvic fractures; T-type fractures, osteosynthesis; fixation techniques; locking plates; Digital Image Correlation 1. Introduction Pelvic fractures (Fig.1a) are classified among the most dangerous ones since they are related to high mortality. In addition the fixation of these fractures is a demanding task given that even the slightest misalignment of the fractured parts during the fi xation operation may cause severe damage of the femur’s cartilage rendering hip artrh oplasty un avoidable. Fixation of pelvic fractures is an extremely complicated operation, as it can be seen in Fig.1b, in which 21st European Conference on Fracture, ECF21, 20-24 June 2016, Catania, Italy ssessing osteosynthesis techniques for pelvic fractures using igital I age Correlation M. Karanika a , D. Georgiou a , S. Darmanis b , Α . Papadogoulas b , E. D. Pasiou a , S. K. Kourkoulis a * a Laboratory of Testing and Materials, Department of Mechanics, Unit of Biomechanics, National Technical University of Athens, 157 73, Greece b NIMITS Hospital, Monis Petraki 10-12, 115 21, Athens, Greece Abstract Various techniques used in orthopedic surgery for the fixation of pelvic fractures are assessed experimentally from the biomech anical point of view. The protocol designed consisted of twenty five experiments with cadaveric semi-pelvises which were artificial ly fractured. The fractures simulated the extremely dangerous T-type ones. Five fixation techniques, comprising of simple and self locking plates with fixation screws, were assessed. For the determination of the displacement field developed three-dimensional Digital Image Correlation (3D-DIC) was used. It was indicated that 3D-DIC is advantageous against classical sensing techniques since it allows convenient selection of critical pairs of material points (both prior and after the experiments, without any limit as to their number) for the estimation of the opening of the fracture. Moreover it permits determination of the pure relative sliding bet ween the various parts of the T-fractured pelvises as it allows isolation of rigid body displacement and rotation. From the clinical point of view it appears that combination of locking reconstruction plates with simple ones offers increased stability. © 2016 The Authors. Published by Elsevier B.V. Peer-review und r responsibility of the Scientific Committee of ECF21. Keywords: pelvic fractures; T-type fractures, osteosynthesis; fixation t chniques; lock ng plates; Digital Image Correlation 1. Introduction Pelvic fractures (Fig.1a) are classified among the most dangerous ones since they are related to high mortality. In addition the fixation of these fractures is a demanding task given that even the slightest misalignment of the fractured parts during the fi xation operation may cause severe damage of the femur’s cartilage rendering hip artrh oplasty un avoidable. Fixation of pelvic fractures is an extremely complicated operation, as it can be seen in Fig.1b, in which Copyright © 2016 The Auth r . Published by Elsevier B.V. This is an open access articl u der the CC BY-NC-ND license (http://cr ativecommons.org/ censes/by-nc- d/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.

* 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 responsibility of the Scientific Committee of ECF21. * Corresponding author. Tel.: +30-210-7721263; fax: +30-210-7721302. E-mail address: stakkour@central.ntua.gr * Corresponding author. Tel.: +30-210-7721263; fax: +30-210-7721302. E-mail address: stakkour@central.ntua.gr

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.2016.06.160