PSI - Issue 2_B

ScienceDirect Available online at www.sciencedirect.com Av ilable o line at ww.sciencedire t.com Sci ceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Struc ural Integrity 2 (2016) 2076–2083 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 The Heat Energy Dissipated in a Control Volume to Correlate the Fatigue Strength of Bluntly and Severely Notched Stainless Steel Specimens Giovanni Meneghetti*, Mauro Ricotta, Bruno Atzori Department of Industrial Engineering, University of Padova, via Venezia, 1, 35131 Padova, Italy Abstract In previously published papers by the authors, the specific heat energy loss per cycle (the Q parameter) was used to rationalize about 120 experimental results generated from constant amplitude, push-pull, stress- or strain-controlled fatigue tests on plain and notched hot rolled AISI 304 L stainless steel specimens as well as from cold drawn un-notched bars of the same steel, tested under fully-reversed axial or torsional fatigue loadings. It has been shown that Q can be estimated starting from the cooling gradient measured at the critical point immediately after the fatigue test has been stopped. Concerning notched specimens, it was noted that a 3 mm notch tip radius was close to the limitation of applicability of the adopted temperature sensor, consisting in 0.127-mm-diameter thermoc uples, bec use of the 1.5-t -2 mm diamet r spo of th glue which prevented to measure he maximum temperature l vel. In this paper, the fatigue-damage- ndex effectiv n ss of Q parameter was i vestigated, carrying out fully eversed axial atigue tests on 4-mm-thick AISI 304L sp cimens, having 3, 1 and 0.5 mm notch tip radii. The c oling gradients were meas red by using an infrared camera, characterized by 20  m/pixels spatial resolution. As a result, all new fatigue data could be rationalized using the same scatter band published previously by the authors. © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21. Keywords: heat energy loss per cycle; energy methods; AISI 304L; fatigue; notch effect; thermography. Copyright © 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND licen e (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the Scientific Com ittee 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.: +0039-049-827-6751; fax: +0039-049-827-6785. E-mail address: giovanni.meneghetti@unipd.it

* 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 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.2016.06.260