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 Procedia Structu al Integrity 8 (2018) 474–485 Available online at www.sciencedirect.com ScienceDirect 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 © 2018 The Authors. Published by Els vier B.V. Peer-review under responsibility of he Scientific Com ittee of AIAS 2017 Intern tiona Confer nce on Str ss Analysis AIAS 2017 International Conference on Stress Analysis, AIAS 2017, 6-9 September 2017, Pisa, Italy Thermoelastic Stress Analysis of modified Transverse Cut Tensile composite specimens under pure Mode II fatigue delamination Giuseppe Pitarresi a,* , Tommaso Scalici b , Giuseppe Catalanotti c a Dipartimento dell’Innovazione Industriale e Digitale - Università degli Studi di Palermo, viale delle scienze Ed. 8, 90128 Palermo, Italy b Dipartimento di Ingegneria Civile, Ambientale, Aerospaziale e dei Materiali - Università degli Studi di Palermo, 90128 Palermo, Italy c School of Mechanical and Aerospace Engineering - Queen’s University Belfast, Belfast BT9 5AH, UK Abstract The present work investigates the behaviour of a Transvers Crack Tensile (TCT) specimen undergoing fatigue loading, by means of a Thermoelastic Stress Analysis (TSA) experimental setup. The TCT is a tensile composite specimen where a number of internal layers are cut through the beam width. The presence of such transverse notch favours the formation of interlaminar Mode II delamin tions, starting from the notch tips and propagating between the cut and continuous plies. In this work, a modification is adopted to the classic TCT specimen, where insert films, mimicking artificial delaminations, are laid across the notch tips. This is done with t purpose to fav ur a pure Mode II and a symmetric and simultane us del mination. The modified-TCT has been subject to cyclic sinusoidal loading, typical of fatigue c aracterisations, and monitored at various crack growth stages by TSA. CFRP and GFRP samples have been prepared and analysed, measuring the thermoelastic signal from the edge and front faces of cycling samples. The information gained from TSA has provided a useful insight on the stress distribution settling near the crack tips, and its evolution with crack growth under fatigue. © 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: Fibre Reinforced Composites, Delamination Fracture Toughness, Mode II, Fatigue, Thermoelastic Stress Analysis. AIAS 2017 International Conference on Stress Analysis, AIAS 2017, 6-9 September 2017, Pisa, Italy Thermoela tic Stress Analysis of modified Transve se Cut Tensile composite specimens under pure Mode II fatigue delamination Giuseppe Pitarresi a,* , Tommaso Scalici b , Giuseppe Catalanotti c a Dipartimento dell’Innovaz one Industrial e Digitale - Un versità degli Studi di Palermo, viale delle sc enze Ed. 8, 90128 Palermo, Italy b Dipartimento di Ingegneria Civile, Ambientale, Aerospazial dei Materiali - Università degli Studi di Palermo, 90128 Palermo, Italy c School of Mechanical and Aerospace Engineering - Queen’s University Belfast, Belfast BT9 5AH, UK Abstract The present work investigates the behaviour of a Transv rs Crack ensile (TCT) specimen und rgoing fatigue loading, by means of a Thermoelastic Stress Analysis (TSA) experime tal setup. The TCT is a tensile composite specimen where a nu ber of internal layers are cut through the beam width. The presence of such transverse notch favours the formation of interla inar Mode II delaminations, starting from the notch tips and propagating between the cut and continu us plies. In this work, a modification i adopted to t classic TCT specimen, where insert films, mi icking artificial delami ations, are laid across the notch tips. Th s is done w th the purpose to favo r a pure Mode II and a symm tr c and simultaneous del minati n. Th modified-TCT has been subject to cyclic sinusoidal loading, typic l of fatigue characterisations, and monitored t various crack g owth stages by TSA. CFRP and GFRP samples have been prepared and an lyse , m asuring the therm elastic signal from the edge and front faces of cycling samples. The information gained from TSA has provided a useful insight on the stress distribution settling near the crack tips, and its evolution with crack growth under fatigue. © 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: Fibre Reinforced Composites, Delamination Fracture Toughness, Mode II, Fatigue, Thermoelastic Stress Analysis.

© 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.: +39 091 23897281. E-mail address: giuseppe.pitarresi@unipa.it * Correspon ing author. T l.: +39 091 23897281. E-mail address: giuseppe.pitarresi@unipa.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.2017.12.047