PSI - Issue 14

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 14 (2019) 597–6 4 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. 2nd International Conference on Structural Integrity and Exhibition 2018 Physical Manifestation of a 90/95 in Remnant Life Revision Studies of Aero-engine Components Vamsi Krishna Rentala a, *, Phani Mylavarapu b , J.P.Gautam a , Gp.Capt.B.V.N.Shiva b , K Gopinath b , Vikas Kumar b a School of Engineeri g Science and Technology, University of Hyderabad, Hyderabad-500046, India b Defence Metallurgical Research Laboratory, Hyderabad-500085, India Damage Tolerance (DT) lifing methodology for aero-engines require the reliability of Non-Destructive Testing (NDT) techniques used. Probability of Detection (POD) for measuring NDT reliability yields the a 90/95 (flaw detection with 90% probability and 95% confidence) value. This a 90/95 or the largest crack size missed by an NDT technique is in general, incorporated into the DT calculations for estimating the remaining fatigue cycles the component can withstand before failure. Hence, it is essential to estimate the a 90/95 value to the closest accuracy. However, the NDT inspection data at a site containing multiple cracks results in ambiguity of HIT/MISS approaches to be adopted for the estimation of POD or a 90/95 values. Several approaches ere attempted by the researchers to mi imize the ambiguity but with limited success ue to the restrictions in impl menting m. Moreover, to the best of the author’s knowledge, the physical significance of the a 90/95 value obtained from differe t HI /MISS approaches on the remnant life calculations of aero-engin components was not ava lable in the literature. Th refore, in the urrent study, physical manifestation of a 90/95 in remna t life calcul tions obtained from the maximum flaw size and sum of flaw sizes approaches for inspection of natural fatigue cracks in a nickel based superalloy using fluorescent penetrant (FPI) and eddy current inspection (ECI) techniques was attempted. It was observed that ECI technique provides the higher number of remnant cycles than the FPI technique due to its higher sensitivity. In addition, it was also observed that regardless of the NDT techniques used, maximum flaw size approach results in higher number of fatigue cycles. However, the actual number of remnant cycles of the component can be exactly known provided the capability of the current NDT techniques in resolving a group of flaws in a particular location is enhanced. 2nd International Conference on Structural Integrity and Exhibition 2018 Physical Manifestation of a 90/95 in Remnant Life Revision Studies of Aero-engine Components Vamsi Krishna Rentala a, *, Phani Mylavarapu b , J.P.Gautam a , Gp.Capt.B.V.N.Shiva b , K Gopinath b , Vikas Kumar b a School of Engineering Sciences and Technology, University of Hyderabad, Hyderabad-500046, India b Defence Metallurgical Research Laboratory, Hyderabad-500085, India Abstract Damage Tolerance (DT) lifing methodology for aero-engines require the reliability of Non-Destructive Testing (NDT) techniques used. Probability of Detection (POD) for measuring NDT reliability yields the a 90/95 (flaw detection with 90% probability and 95% confidence) value. This a 90/95 or the largest crack size missed by an NDT technique is in general, incorporated into the DT calculations for estimating the remaining fatigue cycles the component can withstand before failure. Hence, it is ssential o estimat the a 90/95 value to the closest accuracy. However, the NDT inspectio data at a site containing multiple cracks results in ambiguity of HI /MISS approa hes to be adopted for the estimation of POD or a 90/95 values. Several approaches were attempted by the researchers to minimize the ambiguity but with limited success due to the restrictions in implementing them. Moreover, to the best of the author’s knowledge, the physical significance of the a 90/95 value obtained from different HIT/MISS approaches on the remnant life calculations of aero-engine components was not available in the literature. Therefore, in the current study, physical manifestation of a 90/95 in remnant life calculations obtained from the maximum flaw size and sum of flaw sizes approaches for inspection of natural fatigue cracks in a nickel based superalloy using fluorescent penetrant (FPI) and eddy current inspection (ECI) techniques was attempted. It was observed that ECI technique provides the higher number of remnant cycles than the FPI technique due to its higher sensitivity. In addition, it was also observed that regardless of the NDT techniques used, maximum flaw size approach results in higher number of fatigue cycles. However, the actual number of remnant cycles of the component can be exactly known provided the capability of the current NDT techniques in resolving a group of flaws in a particular location is enhanced. © 2018 The Authors. Published by Elsevier B.V. © 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. © 2019 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) Selection and peer-review under responsibility of Peer-review under responsibility of the SICE 2018 organizers. © 2018 The Authors. Published by Elsevier B.V. Abstract

* Corresponding author. Tel.: +91-9440598223. E-mail address: vamsikrishnarentala@uohyd.ac.in * Corresponding author. Tel.: +91-9440598223. E-mail address: vamsikrishnarentala@uohyd.ac.in

2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. 2452-3216  2019 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) Selection and peer-review under responsibility of Peer-review under responsibility of the SICE 2018 organizers. 10.1016/j.prostr.2019.05.073 2452-3216 © 2018 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) Selection and peer-review under responsibility of Peer-review under responsibility of the SICE 2018 organizers. 2452-3216 © 2018 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) Selection and peer-review under responsibility of Peer-review under responsibility of the SICE 2018 organizers. * Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt