PSI - Issue 14

ScienceDirect Available online at www.sciencedirect.com Av ilable o line at www.sciencedire t.com cienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structu al Integrity 14 (2019) 499–5 6 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 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 Influence of axial constraint on the creep and plastic deformation of a cladding tube Shekhar Suman a *, Sivasambu Mahesh a a Department of Aerospace Engineering, Indian Institute of Technology, Madras, Chennai 600036, India Abstract Tube ballooning of axially confined tubes under increasing thermal loading is studied using a finite element model in an austenitic stainless steel, alloy D9. The model accounts for thermal, plastic and creep deformation of the tube. It is shown that (i) axial restrains can trigger the onset of plasticity, and (ii) activation of plasticity during the thermomechanical loading can significantly reduce the time for the development of large ballooning strains. © 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. Keywords: Ballooning; LOCA; Nuclear fuel cladding; D9 all y; J hnson-Cook plasticity model; creep 1. Introduction Nucl ar fuel cladding encloses the nuclear fuel pellets and acts as a protective shield between fuel pellet and coolant. Clad tube b llooning in th Loss of Coolant Acciden (LOCA) scenario is an important failure mechanism. Ballooning is deleterious because it restricts the coolant flow between the cladding tubes, and thereby reduces heat re oval. The internal pressure and temperature of the clad tube will thus rise because of decay heat of the nuclear fuel. This may lead to thinning of the tube walls and culminate with burst. Tube bursting will contaminate the coolant fluid. Ballooning of axially unrestrained cladding tubes has been extensively investigated in the literature (Neitzel and Rossinger (1980), Manngard and Massih (2011), Massey et al. (2016) and Khan and Pathak (2014)). 2nd International Conference on Structural Integrity and Exhibition 2018 Influence of axial constraint on the creep and plastic deformation of a cladding tube Shekhar Suman a *, Sivasambu Mahesh a a Department of Aerospace Engineering, Indian Institute of Technology, Madras, Chennai 600036, India Abstract T b ballooning of axially confined tubes under i creasing thermal loading is studied using a finite element model in an austenitic stainless steel, alloy D9. The model accounts for thermal, plastic and creep deformation of the tube. It is sh wn that (i) axial restrains can trigger the onset of plasticity, and (ii) activation of plasticity during the thermomechanical loading can significantly reduce the time for the development of large ballooning strains. © 2018 The Authors. Published by Elsevier B.V. This i an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by- c-nd/4.0/) Selection and peer-review under responsibility of Peer-review under responsibility of the SICE 2018 organizers. Keywords: Balloonin ; LOCA; Nuclear fuel cladding; D9 alloy; Joh son-Cook plasticity model; creep 1. Introduction Nuclear fuel cladding e closes the nuclear fuel pellets and acts as a protective shield between fuel pellet and co lant. Clad ub b lloon g in the Loss of Coolant Accid nt (LOCA) scenario is an important failure mechanism. Ball oning is deleterious because it restricts the coolant flow et een the cl dding tubes, and thereby reduces h t removal. The int rnal pressure and temperature of the clad tube will t us rise because of decay heat of the nuclear fuel. This may lead to thinning of the tube walls and culminate with burst. Tub bursting will contaminate th coolant fluid. Ballooning of axially unrestrained cladding tubes has be n extensively investigate in t e literature (Neitzel and Rossinger (1980), Manngard and Massih (2011), Massey et al. (2016) and Khan and Pathak (2014)). © 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.: +91-7358185615 E-mail address: ae15s010@smail.iitm.ac.in * Correspon ing author. Tel.: +91-7358185615 E-mail address: ae15s010@smail.iitm.ac.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.2019.05.060