PSI - Issue 10

ScienceDirect Available online at www.sciencedirect.com Av ilable o line at ww.sciencedire t.com ienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structu al Integrity 1 (2018) 135–14 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2018) 000 – 000

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. © 2018 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/) Peer-review under respon ibility of the scientific committee of the 1st International Conference of the Greek Society of Experimental Mechanics of Materials. 1 st International Conference of the Greek Society of Experimental Mechanics of Materials Multifactorial experimental analysis of concrete compressive strength as a function of time and water-to-cement ratio S. Gavela*, N. Nikoloutsopoulos, G. Papadakos, D. Passa, A. Sotiropoulou School of Pedagogical and Technological Education, Department of Civil Engineering Educators, Maroussi 14121, Greece Abstract Concrete compressive strength is typically tested for fixed nominal values of curing age. Corresponding measurements, even if performed by multiple specimens testing, cannot figure the dispersion of the result attributed to all the significant effective error parameters. This study is a step that aims at the creation of a function that correlates the expected testing result on the compressive strength of concrete specimens to all parameters that will be finally assessed as significant to incorporate. Based on the use of such a multifactorial function, results retrieved from testing procedures that are more loosely defined could be corrected accordingly, in order to be compatible with the strict definition of the testing procedure. Also, the integration of various similar experiments of such a protocol could lead to the standardization of a semi-empirical model on the relation of concrete compressive strength as a functio of a g eat number of testi g paramet rs a d mix mat rials characteristics. This study specifically aims at the experimental investigation a) of t e correlation of compressive trength testing results with the parameters of curing age and wa er to cement ratio through sensitivity analysis and b) of the significance of the cross-correlation between these two parameters. The exp rimental results were used into a multifactorial regression analysis procedure leading to a sigmoidal - by time - equation. The basic outcome of this study is a multifactorial regression function incorporating both the parameters of the curing age and the water to cement ratio for given qualitative characteristics of the constituents. Although this function corresponds to these qualitative characteristics of the constituents, the sensitivity analysis of this study is expected to have a more global validity. Such semi-empirical models, especially if completed with all the significant parameters, are expected to be useful, among others, for accredited testing laboratories in order to perform their internal quality control program. © 2018 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/). Peer-review under responsibility of the scientific committee of the 1 st International Conference of the Greek Society of Experimental Mechanics of Materials performe t l validity. Such semi-empirical models, laboratories in order to perform their internal quality Pu e b Elsevier Ltd. This is an open access article under C ns c-nd © 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. Keywords: Concrete; compressive strength; sigmoidal model; sensitivity analysis

* Corresponding author. Tel.: +30 697 357 9307; fax: +30 210 969 0509 E-mail address: matina@gavela.gr Received: April 30, 2018; Received in revised form: July 20, 2018; Accepted: July 29, 2018

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 Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/) Peer-review under responsibility of the scientific committee of the 1st International Conference of the Greek Society of Experimental Mechanics of Materials. 10.1016/j.prostr.2018.09.020 2452- 3216 © 2018 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/). Peer-review under responsibility of the scientific committee of the 1 st International Conference of the Greek Society of Experimental Mechanics of Materials * Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt