PSI - Issue 13

ScienceDirect Available online at www.sciencedirect.com Available online at ww.sciencedire t.com ScienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structural Integrity 13 (2018) 1756–1761 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2018) 000–000 Available online at www.sciencedirect.com ScienceDirect Structural I t grity 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 Analysis of the statistical size effect model with a critical volume in the range of high-cycle fatigue Tomasz Tomaszewski a * a Institute of Mechanical Engineering, University of Science and Technology, 85-789 Bydgoszcz, Poland Abstract The size effect defined as a relationship between strength properties of the material and specimen cross-section. The study analyses the statistical size effect model with a critical volume. The method is commonly used for objects with different size, including notched specimens and in the bending load tests. The purpose of the study was to verify the size effect model allowing for the loads with gradient and statistically distributed material defects. The analysis model relates the fatigue properties to the material volume. This volume depends on the geometrical dimensions and the specimen volume. For fatigue tests, stress at the specimen surface can be considered a deterministic value defined by the distribution of random variable of failure probability. Fatigue strength is determined for the critical volume at assumed probability. The analyses were carried out for material susceptible to the size effect (acid-resistance steel 1.4301). The tested specimens included a reference specimen and a minispecimen. The selected statistical model was implemented for the experimental data obtained in a high-cycle fatigue range. The method allows to estimate the σ a -N characteristic other than determined experimentally. The model was implemented for a minispecimen. σ a -N characteristic for the reference specimen was estimated based on the model. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. Keywords: minispecimen; stainless steel; analitical model; size effect 1. Introduction The size effect significantly affects the fatigue strength of engineering materials and structural components. The strength is reduced in proportion to the increase in size of an object subjected to fatigue loads (size effect). This strength © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. ECF22 - Loading and Environmental effects on Structural Integrity Analysis of the statistical size effect model with a critical volume in the range of high-cycle fatigue Tomasz Tomaszewski a * a Institute of Mechanical Engineering, University of Science and Technology, 85-789 Bydgoszcz, Poland Abstract The size effect defined as a relationship between strength properties of the material and specimen cross-section. The study analyses the statistical size effect model wit a critical volume. The method is commonly used for objects with different size, including notched specimens and in the bending load tests. The purpose of t e study was to verify the size effect model allowing for the loads with gradient and s tistically distributed material defects. The analysis model relates the fatigue propert es to the material volume. This volume depends on the geometrical dim nsions and the specimen volume. For fatigue tests, stress at the specimen surface can be considere a deterministic value defined by the distribution of rando variable of failure prob bility. Fatigue strength is d termined for the critical volume at assumed probability. The a alyses were carried out for material susceptible to the size effect (acid-resistance steel 1.4301). The tested specimens included a refer nce specimen and a minispecimen. The selected statistical model was implem nted for the experimental data obtaine in high-cy le fatigue range. The method allows to stimate the σ a -N characteristic other than determined exp rimentally. The model was impl mented for a minispecimen. σ a -N characteristic for the reference pecim n w s estimated based on the model. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. Keywords: minispecimen; stainless steel; analitical model; size effect 1. Introduction The size effect significantl affects the fatigue strength of engineering materials and structural components. The strength is reduced in proportion to the increase in size of an object subjected to fatigue loads (size effect). This strength © 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. E-mail address: tomaszewski@utp.edu.pl * Corresponding author. E-mail ad ress: tomaszewski@utp.edu.pl

* Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt 2452-3216 © 2018 The 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 r sponsibility 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.2018.12.372

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