PSI - Issue 13

ScienceDirect Available online at www.sciencedirect.com Av ilable o line at www.sciencedire t.com cienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structural Integrity 13 (2018) 1433–1437 Available online at www.sciencedirect.com ScienceDirect Structural Integrity 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. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. ECF22 - Loading and Environmental effects on Structural Integrity Elements of non-destructive damage monitoring by electrostatic potential method Kiiko V.M. a , Khvostunkov K.A. b , Odzhaev R.K. b a Institute of Solid State Physics of RAS,, Chernogolovka Moscow distr., 142432 Russia b Lomonosov Moscow State University, Moscow, 119992 Russia Abstract We establish a correlati n between the magnitude of a pro agating crack i current-carrying flat samples and the change in the electric potential field over the surface of the sample when an electric current passes through it. The experimental data correspond to an analytic solution obtained using a conformal map in the two-dimensional formulation. This work can be related to the area of converting mechanical quantities into electrical quantities, which simplifies the process of recording mechanical processes and provides a convenient form for controlling and managing them. This work is aimed at the automatic control of the process of the destruction of conductive materials. © 2018 The Authors. Published by Elsevier B.V. Pe r-review under res on ibili y of the ECF22 organizers. Keywords: conducti e sample, electric pot ntial, equipotential line, crack length, conformal map 1. Introduction We study the dependence on the crack length of the electrical potential distribution over the surface of a thin, flat current-conducting specimen along which an electric current passes. The geometry of the pot ential φ field distribution is independent of the magnitude of the current through the specimen, of the specimen conductivity, and of the t mperature. Hence, for example, these quantities do not appear in the Laplace equation Δφ=0 describing the distribution with the corresponding boundary conditions. If the sample contains a crack, then the picture of the distribution of equipotential lines connected with that crack changes as the crack length changes. Registering the change allows establishing a correspondence between the crack length and the position of the equipotential lines. We determine the potential distribution by calculations based on using a conformal map and compare the calculation results with experimental data. This yields a possibility of establishing a one-to-one correspondence between the geometry of the developing crack and the geometry of the electric potential distribution and hence automatic control of experiments on crack propagation in specimen materials and also of real construction in the future. ECF22 - Loading and Environmental effects on Structural Integrity Elements of non-destructive damage monitoring by electrostatic potential method Kiiko V.M. a , Khvostunkov K.A. b , Odzhaev R.K. b a Institute of Solid State Physics of RAS,, Chernogolovka Moscow distr., 142432 Russia b L monosov Mos ow State Univ rsity, Moscow, 119992 Russia Abstract We establish a correlation between the magnitude of a propagating crack in current-carrying flat samples and the change in the electric potential field ver th surface of the sample when an ele tric t passes through it. The experimental data correspond to an analytic solution obt ined using a conformal map in the two-dimensional formulation. This work can be related to the area of converting mechanical quantities into electrical quantities, which simplifies the process of recording mechanical proc sses and pro ides a convenient form for contr lling and man ging them. This work i aimed at the automatic control of the of the destruction of co ductive aterials. © 2018 The Authors. Published by Elsevier B.V. Peer- eview under responsibility of the ECF22 organizers. Keywo ds: c ductive sample, electric potential, equipotential line, crack length, conf rmal map 1. Introduction We study the dependence on the crack length of the electrical potential distribution over the surface of a thin, flat current-co ducting specimen along which a electric curr nt passes. The geometry of the pot ential φ field distributi is independent of the magnitude of the current through the specimen, f the specimen c nductivity, an of the temp rature. Hence, for exa ple, these quantities do not appear in the Laplace equation Δφ=0 describing the distribution with the corresponding boundary conditions. If the sample contains a crack, then the picture of t e istri ti of equipotential li es connected with that crack changes as the crack length changes. Registering t e change allows establishing a correspondence between the crack le th and the position of the equipotential lines. We determine the potential distribution by calculations based on using a conformal map and compare the calculation results with experimental data. This yields a possibility of establishing a one-to-one correspondence between the geometry of the developing crack and the geometry of the electric potential distribution and hence automatic control of experiments on crack propagation in specimen materials and also f real constructi in the future. © 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.: +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 o ganizers.

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.2018.12.297