PSI - Issue 13

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 13 (2018) 232–237 Available online at www.sciencedirect.com ScienceDirect Structural Int grity 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 Root Cause Failure Analysis of Superheated Steam Tube at a Petrochemical Plant Reza Khadem Hosseini * Corrosion Research G oup, Research Institute of Petroleum Industry (RIPI), Tehran, Iran The aim of the present study is to determine root causes of failure in a steam tube at a petrochemical plant. In this order, light microscope and scanning el tro microscope (SEM) were ca ried out observing the microstructures and hardness measurements were used for metallurgical evaluation. In addition, phase composition of deposits were studied by using X-ray diffraction (XRD). Based on the results, “shor t-t erm overheating” was recognized as the root cause of steam tube failure. Metallographic studies showed distributed martensite as a brittle phase in ferritic matrix in the microstructure of damaged area, while in the microstructure of non-damaged area only pearlite and ferrite were seen. These findings were confirmed by hardness measurement results as well. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. Keywords: Failure Analysis; short-term overheating; steam tube 1. Introduction Steam generation and its distribution system are inseparable parts of petrochemical plants that generally operate at high temperatures and pressures. It can lead to several major failures in all parts of system. Corrosion in steam generator units including boilers, and particularly in tubes, is mostly affected by chemistry of water, tubing material susceptibility, operational conditions, e.g. temperature and pressure and thermal and mechanical stresses (Daneshvar Fatah, 2013). Th high temperature damage is the most important failure mechanism in boiler tubes that can occur in different ways, including oxidation, creep, microstructural changes as a result of overheating or interaction with the environment, thermal fatigue, an low cycle fatigue (Le May, 1994). © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. ECF22 - Loading and Environmental effects on Structural Integrity Root Cause Failure Analysis of Superheated Steam Tube at a Petrochemical Plant Reza Khadem Hosseini * Corrosion Research Group, Research Institute of Petroleum Industry (RIPI), Tehran, Iran Abstract The aim of the present study is to determine root causes of failure in a st am tube at a petrochemical plant. In this order, light microscope and scanning el ctron microscope (SEM) w re carried ut obs rving the microstructures and hardness measurements wer used for metallurgical evaluation. In addition, phase composition of deposits were studied y using X-ray diffraction (XRD). Based on the results, “shor t-t erm overheating” was re ognized as the root cause of ste tube failure. Metallographic studies showed distributed martensite as a brittle phase in ferritic matrix i the microstructure of damaged area, while in the microstructure of non-damaged area only pearlite and ferrite were seen. These findings were confirmed by hardness measurement results as well. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. Keywords: Failure Analysis; short-term overheating; steam tube 1. Introduction Steam generation and its distribution system are inseparable parts of petrochemical plants that generally operate at high temperatures and pressures. It can lead to several major failures in all parts of system. Corrosion in steam generator units including boilers, and particularly in tubes, is mostly affected by che istry of water, tubing material susceptibility, operational conditions, e.g. temperature and pressure and thermal and mechanical stresses (Daneshvar Fatah, 2013). The high temperature damage is the most important failure mechanism in boiler tubes that can occur in diff rent ways, including oxidation, cr ep, microstructural changes as a result of overheating or interaction with the environment, thermal fatigue, and low cycle fatigue (Le May, 1994). © 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.: +9821 4825 5204 E-mail address: hosseinir@ripi.ir * Correspon ing author. Tel.: +9821 4825 5204 E-mail address: hosseinir@ripi.ir

* Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt 2452 3216 © 2018 Th 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 responsibility of the ECF22 organizers.

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.2018.12.039