PSI - Issue 3

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 Structu al Integrity 3 (2017) 45 –458 Available online at www.sciencedirect.com Sc enceDir ct Structural Integrity 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 © 2017 The Auth rs. Publis ed by Elsevier B.V. This is an open access article u der the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the Scientific Committee of IGF Ex-Co. XXIV Italian Group of Fracture Conference, 1-3 March 2017, Urbino, Italy An investigation on the “width and size effect” in the evaluation of the fracture energy of concrete Christian Carloni a , Mattia Santandrea a *, Roman Wendner b a University of Bologna-DICAM, Viale Risorgimento 2, Bologna 40136, Italy b University of Natural Resources and Life Sciences-Christian Doppler Laboratory LICROFAST, Peter-Jordan-Straße 82, Wien 1190, Austria Abstract The parameters that describe the fracture behavior of concrete are crucial to investigate numerically the response of reinforced concrete (RC) structures. Among them, the fracture energy plays a key role in all those applications that aim to simulate the behavior of RC structures. The fracture energy is a characteristic property of a material but its experimental evaluation could be difficult for quasi-brittle materials such as concrete due to the “width effect” and “size effect” that can lead to some uncertainties in the definition of this parameter. This study presents the results of an experimental campaign conducted on notched specimens to evaluate the fracture energy of concrete. Concrete prisms with different size were tested using a three-point bending (TPB) s t-up to evaluate th influence of the width and the size on the result . The setup has been designed to bec me potentially part of the ACI 446 report on fracture. Digital image correlation (DIC) was used to qualitatively and quantitatively study the strain field near the crack tip. Preliminary numerical simulations were performed to investigate the “width effect” in a discrete element framework. © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of IGF Ex-Co. Keywords: Fracture mechanics; concrete; fracture energy; width effect; size effect. 1. Introduction The tensile strength and the fracture parameters of concrete are important properties of concrete when the anchorage of def med bars, shear forces in slabs and beams, splitting under concentrated forces, unreinforced pipes, and bond of composite materials (Carloni, 2014) are investigated. Although the influence of these properties on the behavior of XXIV Italian Group of Fracture Conference, 1-3 March 2017, Urbino, Italy An investigation on the “width and size effect” in the evaluation of the fracture energy of concrete Christian Carloni a , Mattia Santandrea a *, Roman Wendner b a University of Bologna-DICAM, Viale Risorgime to 2, Bolo na 40136, Italy b University of Natural Resources and Life Sciences-Christian Doppler Laboratory LICROFAST, Peter-Jordan-Straße 82, Wien 1190, Austria Abstract The parameters that describe the fracture behavior of concrete are crucial to investigate numerically the response of reinforced concrete (RC) tructur . Among them, th fracture energy plays k y ole in all those applications that aim to simulate the behavior of RC structures. The fracture energy is a ch racteristic property of a mat rial but it experimental evaluation could be difficult f quasi-brittle materials su h as concrete due to the “width effect” and “size ffect” that can lead to some uncertainties in the definiti n of this parameter. Thi study presents th results of an xperimental campaign conduct d on n tched spec mens to evaluate the fracture energy of concrete. Concr te prisms wi h differ nt sizes were tested using a thre -p int bending (TPB) set-up to evaluat the influ ce of the width and th size on the results. Th setup has b en designed t be ome po entially part of th ACI 446 report on fracture. Digital image correlat on (DIC w s used to qualitatively nd quanti atively study the strain field near the crack tip. Prelimin ry umerical simulations were performed to investigate th “wi t effec ” n a di cr t element framework. © 2017 The Authors. Published by Els vi B.V. Peer-review under responsibility of the Scie tific Committee of IGF Ex-Co. Keywords: Fracture mechanics; concrete; fracture energy; width effect; size effect. 1. Introduction The tensile strength a d the fracture parameters of concrete are important properties of concrete when the anchorage of deformed bars, shear forc s in slabs nd b ams, splitting under conce rated forces, unreinforced pipes, and bond composite mat rials (Carlon , 2014) re investigated. Although the infl ence of th e properties on th behavior of © 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.: +39 051 20 9 3375. E-mail address: mattia.santandrea3@unibo.it * Corresponding author. Tel.: +39 051 20 9 3375. E-mail address: mattia.santandrea3@unibo.it

* Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt 2452-3216 © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of IGF Ex-Co. 2452-3216 © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of IGF Ex-Co.

2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. Copyright © 2017 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 IGF Ex-Co. 10.1016/j.prostr.2017.04.065