PSI- Issue 9

ScienceDirect Available online at www.sciencedirect.com Av ilable o line at ww.sciencedirect.com ienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structu al Integrity 9 (2018) 303–31 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

www.elsevier.com/locate/procedia 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 B.V. Peer-review under responsibility of the Gruppo Italiano Frattura (IGF) ExCo. IGF Workshop “Fracture and Structural Integrity” Feasibility and effectiveness of exoskeleton structures for seismic protection Anna Reggio a, *, Luciana Restuccia a , Giuseppe Andrea Ferro a a Department of Structural, Geotechnical and Building Engineering, Politecnico di Torino, Turin, Italy Abstract In this study, a self-supporting structure, namely an exoskeleton , is considered as set outside a main structure and suitably connected to it. From the structural point of view, the exoskeleton is conceived as a “sacrificial” appendage, called to absorb seismic loads in order to increase the performance of the main structure. From the architectural and technological point of view, additional functions may be associated through an integrated design approach, combining seismic with urban and energy retrofitting. Particular and attractive applications can therefore be envisaged for existing buildings. A reduced-order dynamic model is introduced, in which two coupled linear viscoelastic oscillators represent the main structure and the exoskeleton structure, respectively, while either a rigid link or a dissipative viscoelastic connection is considered for the coupling. T e equations of tion are set in non-dimensional form and a parame ric study s carried out i the fr quency domain to confirm that exoskeleton structures can be fe sible and effective in reducing earthquake-induced dynamic responses. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Gruppo Italiano Frattura (IGF) ExCo. Keywords: seismic protection, structural control, external retrofitting, exoskeleton structure, coupling. 1. Introduction The concept of s ismic resilience (Bruneau et al. 2003) has been recently responsible for a paradigm shift in seismic design and risk management: other objectives beyond life and collapse safety, such as operational continuity (Parise et al. 2013, Parise et al. 2014), damage control and loss re uction, are considered as crucial to substantially enhance IGF Workshop “Fracture and Structural Integrity” Feasibility and effectiveness of exoskeleton structures for seismic protection Anna Reggio a, *, Luciana Restuccia a , Giuseppe Andrea Ferro a a Department of Structural, Geotechnical and Building Engineering, Politecnico di Torino, Turin, Italy Abstract In this study, a self-s pporting structure, namely an exoskeleton , s considered as set outsid a main structure and suitably connected to it. From the structural point of view, the exoskeleton is conceived as a “s crificial” appendage, called to absorb seismic loads in order to increase the performance of the main structure. From the architectural and technological point of view, additional f nctio s may be associated through an integrated desi n approach, combini seismic with urban and energy retrofitting. Particular and att activ applicatio s can ther fore be envisaged for existing b i dings. A reduced-order dynamic model is introduced, in which two coupled linear viscoelastic oscillators represent the main st ucture and the exoskeleton structure respectively, while e ther a rigid link or a dissipative vi oela tic connectio is considered f r the c upling. T e equations f mo ion are set in non-dime sional form and a param tric tudy is carrie out in he frequ ncy omain to confirm that exoskeleton stru tures can be fea ible and effective in reducing earthquake-induced dynamic r sp nses. © 2018 The Authors. Publ shed by Elsevier B.V. Peer-review under responsibility of the Gruppo Italiano Frattura (IGF) ExCo. Keywords: seismic protection, structural control, external retrofitting, exoskeleton structure, coupling. 1. Introduction The concept of seismic resilience (Bruneau t al. 2003) has been recently responsible f r a paradigm shift in seismic design and risk management: oth r objectives b yo d life and collapse safety, such as operational co tinuity (P ris et al. 2013, Parise et al. 2014), damage control and loss reduction, are considered as crucial to substantially enhance © 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.: +39 011 0904844. E-mail address: anna.reggio@polito.it * Correspon ing author. Tel.: +39 011 0904844. E-mail address: anna.reggio@polito.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. Peer-review under responsibility of the Gruppo Italiano Frattura (IGF) ExCo. 10.1016/j.prostr.2018.06.020 * 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 Gruppo Italiano Frattura (IGF) ExCo. 2452-3216 © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Gruppo Italiano Frattura (IGF) ExCo.