PSI - Issue 14

ScienceDirect Available online at www.sciencedirect.com Av ilable o line at www.sciencedire t.com Sci ceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structu al Integrity 14 (2019) 688–695 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. © 2019 Th Authors. Published by Elsevier B.V. This is an open access art cle 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. 2nd International Conference on Structural Integrity and Exhibition 2018 Failure analysis of structural screw joint in a start-up neutron detector handling mechanism Sudheer Patri*, Hemant Kumar, K. Krishna Prasad, C. Meikandamurthy, B. K. Sreedhar, R. Vijayashree, V. Prakash, P. Selvaraj Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102, India Abstract This paper deals with the failure analysis of a structural screw joint located in the load transfer path of a complex mechanism called Start-up Neutron Detector Handling Mechanism (SNDHM). It is a carrier mechanism for high temperature neutron detectors, which measure the neutron flux during initial criticality. In installation testing of SNDHM, failure was observed in all the 6 no’s of M5 screws of this structural joint. These screws were as per standard IS 1367-3 with property class 12.9. Subsequently, these failed screws were analysed to find out the root cause of failure, so that necessary measures can be adopted to prevent such failure in future. Chemical analysis from EDS indicated deviation in chemical composition of screw material from the standard. Hardness tests results revealed an average hardness of 229 HV 10 against specified value of 356 – 414 HV 10 . Based on the hardn ss values, which is nearly 40% lower than he expected value, it is assumed that the estimated strength of he screws would be much lower than the specified values as per standard. This implie that the joint has failed at load, which is much lower than the designed value. However, the possibility of over load either due to errors in packing or du to abnormal operation cannot be ignored. It is postulated t at the un-noticed motor ver-travel during final stages of testing or packing errors would have resulted in over load. It is proposed to incorporate a torque limiter in the drive line of the mechanism to prevent over loading due to erroneous motor operation in future, apart from use of screws which comply with the standard. © 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. 2nd International Conference on Structural Integrity and Exhibition 2018 Failure analysis of structural screw joint in a start-up neutron detector handling mechanism Sud er Patri*, Hema t Kumar, K. Krishna Prasad, C. M ikandam thy, B. K. Sr edhar, R. Vijayashree, V. Prakash, P. Selvaraj Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102, India Abstract This pape deals wi h the failure analysis of a structural screw joint located in the load tr sfer path of a complex m chanism call d Start-up Neutron Detector Handling Mechan sm (SNDHM). It is carri r mechanism for h gh temperature neutron detectors, which measure the neutron flux during initial criti ality. In inst llation testing of NDHM, fa lure was observed in all the 6 no’s of M5 screws of this st uctural joint. These scr ws were as per standard IS 1367-3 with property class 12.9. Subs quen ly, these failed screws were an ysed to find out the root use of f ilure, so t at necessary measures can be adopted to prev nt such failure i future. Chemical analysis from EDS indicated deviation in chemical composition of screw material from the stand . H rd ess tests results rev aled an averag hardn s of 229 HV 10 against specified value f 356 – 414 HV 10 . Based on the ardness values, which is nearly 40% lower tha the expected value, it i assum d that t e est mated s rength of the screws would be much lower th n the specified values as p r standard. T is implies that the j t has fail d at load, which is much l wer than the designed value. However, h possib lity of over lo d either due to errors in packing or due to abno mal operation cannot be gn r d. It is postulated that the un-n tic d motor over-travel during final stages of testi g or packing errors would hav resulted in over l ad. It is proposed to inco porate a torque limiter in the drive line of the mechanism to prevent over loading due to erroneous motor operation in future, apart from use of screws which comply with the standard. © 2018 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND lic nse (https://creat vecommons.org/licenses/by- c-nd/4.0/) Selection and peer-review under responsibility of Peer-review under responsibility of the SICE 2018 organizers.

© 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. Keywords: SNDHM; screwed joint failure; failure analysis. Keywords: SNDHM; screwed joint failure; failure analysis.

Keywords: High Pressure Turbine Blade; Creep; Finite Element Method; 3D Model; Simulation.

* Corresponding author. Tel.: +91-44-27480211 ; fax: +91-44-27480152. E-mail address: patri@igcar.gov.in * Correspon ing author. Tel.: +91-44-27480211 ; fax: +91-44-27480152. E-mail address: patri@igcar.gov.in

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 a open access article und r the CC BY-NC-ND lic nse (https://creat vecommons.org/licenses/by- c-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

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.2019.05.086