PSI - Issue 12

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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. AIAS 2018 International Conference on Stress Analysis Crack Propagation Analysis of Near-Surface Defects with Radial Basis Functions Mesh Morphing Francesco Giorgetti* a , Riccardo Cenni b , Andrea Chiappa a , Matteo Cova b , Corrado Groth a , Edoardo Pompa a,c , Stefano Porziani a , Marco Evangelos Biancolini a a University of Rome ”Tor Vergata”, Via del Politecnico 1, Rome 00133, Italy b SACMI Imola S.C. - Ceramic Engineering Department,Via Selice Provinciale, 17 / A, Imola 40026, Italy c Fusion for Energy, c / Josep Pla, n.2, Torres Diagonal Litoral, Edificio B3, E-08019, Barcelona, Spain Abstract Fracture mechanics analysis is now days adopted in several industrial fields to assess the cap bility f components to withstand fatigue loads. Finite Element Method (FEM) is a well-established tool for the evaluation of flaw Stress Intensity Factors (SIF) and for the survey of its propagation. Nevertheless the study of the growth of near-surface circular and elliptical cracks is still an arduous task to be faced with FEM. In fact, the interaction of the flaw with free surfaces leads the crack front to assume complex shapes, whose simulation cannot be easily accomplished. A possible answer to deal with such a problem is to use the mesh morphing technique, a nodal relocation methodology, that allows to cover di ff erent problems. In fact, with mesh morphing, it is possible to fit the baseline flaw front with the desired shape (generic shape) and to automatically simulate its evolution at a certain number of cycles. In the proposed work this approach is demonstrated exploiting ANSYS Mechanical as FEM tool and RBF Morph ACT Extension as mesh-morpher. The results of the proposed workflow are compared with those available in literature. c 2018 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 / 3.0 / ) Peer-review under responsibility of the Scientific Committee of AIAS 2018 International Conference on Stress Analysis. Keywords: Near Surface Crack; Radial Basis Functions; Automatic Crack Propagation; Mesh Morphing © 2018 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/3.0/) Peer-revi w und r responsibility of the Scientific Committee of AIAS 2018 Internat onal Conference n Stress Analysis. AIAS 2018 International Conference on Stress Analysis Crack Propagation nalysis of ear-Surface efects ith Radial Basis Functions esh orphing Francesco Giorgetti* a , Riccardo Cenni b , Andrea Chiappa a , atteo Cova b , Corrado Groth a , Edoardo Pompa a,c , Stefano Porziani a , a co Evangelos Biancolini a a University of Rome ”Tor Vergata”, Via del Politecnico 1, Rome 00133, Italy b SACMI Imola S.C. - Ceramic Engineering Department,Via Selice Provinciale, 17 / A, Imola 40026, Italy c Fusion for Energy, c / Josep Pla, n.2, Torres Diagonal Litoral, Edificio B3, E-08019, Barcelona, Spain Abstract Fracture mechanics analysis is nowadays adopted in several industrial fields to assess the capability of components to withstand fatigue loads. Finite Element Method (FEM) is a well-established tool for the evaluation of flaw Stress Intensity Factors (SIF) and for the survey of its propagation. Nevertheless the study of the growth of near-surface circular and elliptical cracks is still an arduous task to be faced with FEM. In fact, the interaction of the flaw with free surfaces leads the crack front to assume complex shapes, whose simulation cannot be easily accomplished. A possible answer to deal with such a problem is to use the mesh morphing technique, a nodal relocation methodology, that allows to cover di ff erent problems. In fact, with mesh morphing, it is possible to fit the baseline flaw front with the desired shape (generic shape) and to automatically simulate its evolution at a certain number of cycles. In the proposed work this approach is demonstrated exploiting ANSYS Mechanical as FEM tool and RBF Morph ACT Extension as mesh-morpher. The results of the proposed workflow are compared with those available in literature. c 8 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY C-ND licen e (http: // creat ve mmons.org / licenses / by-nc-nd / 3.0 / ) i w unde responsibility of the Sc entific Committee of AIAS 2018 International Conferenc on Stress Analysi . Keywords: Near Surface Crack; Radial Basis Functions; Automatic Crack Propagation; Mesh Morphing

© 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. 1. Intro uction

1. Introduction

The knowledge of fracture behaviour is of crucial relevance in several industrial fields in order to prevent sudden breaks. The fracture mechanics theory is based on the assumption that all real materials contain cracks of some size. For this reason the study of the fracture mechanics is of great importance for life prediction of components subjected The knowledge of fracture behaviour is of crucial relevance in several industrial fields in order to prevent sudden breaks. The fracture mechanics theory is based on the assumption that all real materials contain cracks of some size. For this reason the study of the fracture mechanics is of great importance for life prediction of components subjected

* Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt ∗ Corresponding author. Tel.: + 39 06 72597136 E-mail address: francesco.giorgetti@uniroma2.it ∗ Corresponding author. Tel.: + 39 06 72597136 E-mail address: francesco.giorgetti@uniroma2.it

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. 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 AIAS 2018 International Conference on Stress Analysis. 10.1016/j.prostr.2018.11.071 2210-7843 c 2018 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 / 3.0 / ) Peer-review under responsibility of the Scientific Committee of AIAS 2018 International Conference on Stress Analysis. 2210-7843 c 2018 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 / 3.0 / ) Peer-review under r ponsibility of the Scientific ommitt e of AIAS 2018 International Conference on Stress Analysis.