PSI - Issue 8

ScienceDirect Available online at www.sciencedirect.com Av ilable o line at ww.sciencedire t.com ScienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 P o edi Structural Integr ty 8 (2018) 83–91 Available online at www.sciencedirect.com ScienceDirect Structural Int grity Procedia 00 (2017) 000 – 000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2017) 000 – 000

www.elsevier.com/locate/procedia 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. Copyright © 2018 The Authors. ublished by E sevier B.V. Peer-review und responsibility of the Scientific Co mittee of AIAS 2017 International Con erence on Stress Analysis AIAS 2017 International Conference on Stress Analysis, AIAS 2017, 6-9 September 2017, Pisa, Italy Catadioptric stereo-vision system using a spherical mirror S. Barone a , P. Neri a, *, A. Paoli a and A. V. Razionale a a University of Pisa, Department of Civil and Industrial Engineering, Largo L. Lazzarino 1, Pisa 56122, Italy Abstract In the computer vision field, the reconstruction of target surfaces is usually achieved by using 3D optical scanners assembled integrating digital cameras and light emitters. However, these solutions are limited by the low field of view, which requires multiple acquisition from different views to reco struct complex free-fo m geometries. The combination of mirror and lenses (catadioptric systems) can be adopted to overcome this issue. In this work, a stereo c tadioptric optical scanner has been developed by assembling two digital cameras, a spherical mirror and a multimedia white light projector. The adopted configuration defines a non-single viewpoint system, thus a non-central catadioptric camera model has been developed. An analytical solution to compute the projection of a scene point onto the image plane (forward projection) and vice-versa (backward projection) is presented. The proposed optical setup allows omnidirectional stereo vision thus allowing the reconstruction of target surfaces with a single acquisition. Preliminary results, obtained measuring a hollow specimen, demonstrated the effectiveness of the described approach. © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of AIAS 2017 International Conference on Stress Analysis. Keywords: 3D acquisition; structured light scanning; catadioptric stereo vision system; spherical mirror projection model; internal geometries acquisition AIAS 2017 International Conference on Stress Analysis, AIAS 2017, 6-9 September 2017, Pisa, Italy Catadioptric stereo-vision system using a spherical mirror S. Barone a , P. Neri a, *, A. Paoli a and A. V. Razionale a a University of Pisa, Department of Civil and Industrial Engineering, Largo L. Lazzarino 1, Pisa 56122, Italy Abstract I the computer vision field, the reconstruction of target surfaces is usually achieved by using 3D optical scanners assembled integrating digital ca ras and light mitters. However, th se solutions are limit d by the low field of view, which requires multiple acquisition from ifferent views to reconstruct complex free-form geometries. The combination of mirrors and lenses (catadioptric systems) can be adopted to overco e this issue. In this work, a st reo catadioptric optical scanner has been developed by assembling two digital cameras, a spherical mirror nd a multimedia white lig t projector. The a opted configurati n defines a non-singl viewpoint system, thus a n -central c tadioptric camera mod l has been developed. An analytical solution to compute t r jection of a scene point ont the image plane (f rward projection) a d vice-versa (backward proj ction) is presented. Th proposed optical setup allows omnidirectional stereo vision thus allowing the reconstruction of target surfaces with a single acquisition. Preliminary results, obtained measuring a hollow specimen, demonstrated the effectiveness of the described approach. © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of AIAS 2017 International Conference on Stress Analysis. Keywords: 3D acquisition; structured light scanning; catadioptric stereo vision system; spherical mirror projection model; internal geometries acquisition © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. The 3D reconstructi of mechanical parts is widely used in many branches of modern manufacturing industry to create digital models. In general, the shape of an existing physical model can be retrieved by using contact techniques The 3D reconstruction of mechanical parts is widely used in many branches of modern manufacturing industry to create digital models. In general, the shape of an existing physical model can be retrieved by using contact techniques Keywords: High Pressure Turbine Blade; Creep; Finite Element Method; 3D Model; Simulation. 1. Introduction 1. Introduction

* Corresponding author. Tel.: +39-050-2218019; fax: +39-050-2218065. E-mail address: paolo.neri@dici.unipi.it * Correspon ing author. Tel.: +39-050-2218019; fax: +39-050-2218065. E-mail address: paolo.neri@dici.unipi.it

2452-3216 © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of AIAS 2017 International Conference on Stress Analysis. 2452 3216 © 2017 Th Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of AIAS 2017 International Conference on Stress Analysis.

* 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.

2452-3216 Copyright  2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of AIAS 2017 International Conference on Stress Analysis 10.1016/j.prostr.2017.12.010