PSI - Issue 13

ScienceDirect Available online at www.sciencedirect.com Available o line at ww.sciencedire t.com ienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structural Integrity 13 (2018) 21 1–21 8 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2018) 000–000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2018) 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. ECF22 - Loading and Environmental effects on Structural Integrity Experimental investigation of the displacement field in a circular disc drilled eccentrically Ermioni D. Pasiou, Stavros K. Kourkoulis*, Maria G. Tsousi, Christos F. Markides Laboratory for Testing and Materials, Department of Mechanics, School of Applied Mathematical and Physical Sciences, National Technical University of Athens, Theocaris Building, Zografou Campus, 157 73 Athens, Greece Abstract The aim of the present study is to experimentally quantify the role of potential eccentricities of the ring’s hole on the overall displacement field developed in a circular ring under diametral compression. In this context, circular rings, made of PMMA, were subjected to diametral compression using the device suggested by the International Society for Rock Mechanics (ISRM) for the standardized implementation of the Brazilian-disc test. The specimens were circular discs, drilled throughout their thickness, forming either perfect rings (zero eccentricity) or discs with an eccentric hole. The parameters considered included the angle, θ, between the line of centers and the loading axis and the distance, d, between the centers of the disc and the hole. The displacement field developed all over the surface of the spe imens was determined u ing the 3D Digital Imag Correlation (DIC) technique. The experi m ntal protocol proved that for small and medium values of the parameter d t influence of eccentricity is described by a lin ar law in pen ently of the value of angl θ, while for relatively high d-values the phenomenon becomes strongly non-linear. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. Keywords: Brazilian-disc test; ring test, eccentricity, displacement field; Digital Image Correlation; PMMA 1. Introduction The familiar Brazilian-disc test was proposed independently (although simultaneously) by Carneiro (1943) and Akazawa (1943), as a convenient substitute of th direct ension test, in case specimens made of very brittle materials (mainly rock-like ones and concrete) were to be tested. Nowadays, the specific test is widely used worldwide although © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. ECF22 - Loading and Environmental effects on Structural Integrity Experimental investigation of the displacement field in a circular disc drilled eccentrically Ermioni D. Pasiou, Stavros K. Kourkoulis*, Maria G. Tsousi, Christos F. Markides Laboratory for Testing and Materials, Department of Mechanics, School of Applied Mathematical and Physical Sciences, Nati nal Technical University of Athens, Theocaris Building, Zografou Campus, 157 73 Athens, Greece Abstract The aim of the present study is to experimentally quantify the role of potential eccentricities of the ring’s hole on the overall displ cement field d veloped in a circular ring under diametral compression. In this context, circular rings, made of PMMA, were subject d to diametral c mpression using the device sugg sted by the International Society for Rock Mechanics (ISR ) for th tandardized implementation of the Brazilian-disc test. The specimens were circular discs, drilled throughout t eir thickness, forming either perfect rings (zero eccentricity) or discs with an eccentric hole. The parameters considered included the angle, θ, between the line of centers and the loading axis and the distance, d, between the centers of the disc and the hole. The displacement field developed all over the surface of the specimens was determined using the 3D Digital Image Correlation (DIC) technique. Th experi mental protoc l proved that for small and edium valu s of the par meter d the influence of ecc ntricity is describ d by a lin ar law independently of the value of angle θ, while for relatively high d-v lu s the phe omenon becomes strongly non-linear. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. Keywords: Brazilian-disc test; ring test, eccentricity, displacement field; Digital Image Correlation; PMMA 1. Introduction The familiar Brazilia -d sc tes was proposed indep ndently (although simultaneously) by Carneiro (1943) and Akazawa (1943), as a convenient substitute of the direct tension test, in case specimens made of very brittle materials (mainly rock-like ones and concrete) were to be tested. Nowadays, the specific test is widely used worldwide although © 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 © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. 2452-3216 © 2018 The Authors. Published by Elsevier B.V. Peer review under r sponsibility of the ECF22 organizers. * Corresponding author. Tel.: +30-210-772-1263; fax: +30-210-772-1302. E-mail address: stakkour@central.ntua.gr * Corresponding author. Tel.: +30-210-772-1263; fax: +30-210-772-1302. E-mail ad ress: s akkour@central.ntua.gr

2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016.

2452-3216  2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. 10.1016/j.prostr.2018.12.201