PSI - Issue 2_A

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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 Fract re of high-density polyethylene used for bleach bottles M. Contino a , L. Andena a *, M. Rink a , A. Colombo a , G. Marra b a Dipartimento di Chimica,Materiali e Ingegneria Chimica “G.Natta”, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy b Fater S.p.A., R&D division,Via Ardeatina 100, 00071 Pomezia,Italy High-density polyethylene (HDPE) can be blow-molded and used for the production of bottles for aggressive products. These products can interact both ch mically a d physically with the p lymer nstituting thes cont iners, leading to a decrease in the performance of the material and undermining the structural integrity of the component. A fracture mechanics approach was adopted to evaluate the Environmental Stress Cracking Resistance (ESCR) of two HDPE commercial grades used for bleach containers; two different solutions, with and without sodium hypochlorite (the main ingredient of commercial bleach solutions), were considered as aggressive environments. Size effects were studied using different test configurations and loading histories in air. The correlation between the stress intensity factor and the initiation time was found. A clear effect of the aggressive solutions on the fracture resistance of the two HDPEs was observed, irrespective of the presence of sodium hypochlorite; the effect therefore has to be ascribed to other bleach components. © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21. Keywords: Polyethylene; Environmental Stress Cracking; Fracture mechanics; Bleach 1. Introduction High-density p lyethylen (HDPE) is a polymer widely used for packaging applications, such as bottles for household detergents. One of these products is bleach, an alkaline aqueous solution of sodium hypochlorite, which can also contain perfumes and surfactants. Once filled with the product, these containers are packed on pallets, which in turn are stacked one on top of the other. The containers at the bottom may be subjected to very high mechanical stresses due to the weight of the 21st European Conference on Fracture, ECF21, 20-24 June 2016, Catania, Italy Fracture of high-density polyethylene used for bleach bottles M. Contino a , L. Andena a *, M. Rink a , A. Colombo a , G. Marra b a Dipartimento di Chi ica,Materiali e Ingegneria Chimica “G.Natta”, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy b Fater S.p.A., R&D division,Via Ardeatina 100, 00071 Pomezia,Italy Abstract High-density polyethylene (HDPE) can be blow-molded and used for the production of bottles for aggressive products. These products can interact both chemically and physically with the polyme constituting these containers, leading to a decrea e in th erformance of the material and undermining the structural integrity of the component. A fracture mechanics appro ch was adopted to evaluate the Environmental Stress Cracking Resistance (ESCR) of two HDPE commercial grades u ed for bleach containers; two differ nt solutions, with nd without sodium hypochlorite (the main ingredient of commercial bleach solutions), were con idered as aggressive environments. Size effects were studied using different t st configur tions and loading histories in air. The correlation b tween the stress i tensity factor and th initiation time was found. A lear effect of the aggressive lutions on the fracture resistanc of t two HDPE was observed, irrespective of the presence of sodium hyp chlorite; the effect therefore has to be ascribed to other bl ach components. © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21. Keywords: Polyethylene; Environmental Stress Cracking; Fracture mechanics; Bleach 1. Introduction High-density polyethylene (HDPE) is a polymer widely used for packaging applications, such as bottles for househol d tergents. One of these products is bleach, an alkaline aqueous solution of sodium hypochlorite, which can als contain perfumes and surfactants. Once filled with the product, these containers are packed on pallets, which in turn are stacked one on top of the other. The conta ners at the bot om may be subjected to very high mec anical st esses due to the weight Copyright © 2016 The Authors. Published by Elsevier B.V. This s an op n access article under the CC BY-NC-ND licens (http://creativecommons. rg/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the Scientific Co mittee 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. Abstract

* 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 ECF21. * Corresponding author. Tel.: +390223993289; fax: +390223993280. E-mail address: luca.andena@polimi.it * Corresponding author. Tel.: +390223993289; fax: +390223993280. E-mail address: luca.andena@polimi.it

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.2016.06.028