PSI - Issue 5

ScienceDirect Available online at www.sciencedirect.com Av ilable o line at ww.sciencedire t.com cienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structural Integrity 5 (2017) 689–696 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2017) 000 – 000 ScienceDirect Structural Integrity Procedia 00 (2017) 000 – 000

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www.elsevier.com/locate/procedia 2nd International Conference on Structural Integrity, ICSI 2017, 4-7 September 2017, Funchal, Madeira, Portugal Numerical Analysis of Bird Strike Resistance of Helicopter Searchlight Sebastian Heimbs a, *, Ulrich Fischer b , Willy Theiler b , Frederik Steenbergen b a Airbus Group Innovations, 81663 Munich, Germany b RUAG Aviation, 6032 Emmen, Switzerland Bird strike is a major threat to aircraft structures, as a collision with a bird during flight can lead to serious structural damage. For helicopters the windshield, forward airframe structure, r tor blades a d all exterior equipment parts are exposed to the risk of bird impact. Consequently, aviation authorities require that such structures need to prove bird strike resistance before they are allowed for operational use, which primarily had to be demonstrated in full-scale bird impact tests in the past. Today, as numerical simulation techniques have evolved and proven accuracy, compliance can more and more be shown by sufficiently validated numerical analyses. This study shows such an example of successful simulative demonstration of bird strike resistance of a searchlight and its pod as external equipment of a military helicopter. The finite element model was built up and validated step by step according to the building block approach from coupon level up to the full-scale structural level. The focus was on the accurate non-linear constitutive modeling of the different aluminum alloys and mechanical fasteners of the target structure. The searchlight pod as well as its internal electrical components and attachments were modelled with a high level of detail in order to allow for accurate results evaluations. A validated smoothed particle hydrodynamics (SPH) bird impactor model was used to simulate different load cases and impact positions of this fluid-structure interaction scenario with a water-like soft body projectile. Although plastic deformations and partial fracture of the outer housings of the structure were observed, no critical failure mod , detachment of critical pa ts or loss of structural integrity occur ed. These alyses were a c pted by the auth rities as m ans of complianc and demonstrat tod y’s progress in airwort hiness cer ification by simulation. © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ICSI 2017. 2nd International Conference on Structural Integrity, ICSI 2017, 4-7 September 2017, Funchal, Madeira, Portugal Num rical Analysis of Bird Strike Resistance of Helicopter Searchlight Sebastian Heimbs a, *, Ulrich Fischer b , Willy Theiler b , Frederik Steenbergen b a Airbus Group Innovations, 81663 Munich, Germany b RUAG Aviation, 6032 Emmen, Switzerland Abstract Bird strike is a major threat to aircraft structures, as a collision with a bird during flight can lead to serious structural damage. For helicopters the windshield, forward airframe structure, rotor blades and all exterior equipment parts are exposed to the risk of bird impact. Consequently, aviation authorities require that such structures need to prove bird strike resistance before they are allowed for ope tional use, which primarily had to be demonstrated in full-scale bird impact tests in the past. Today, as numerical simulation techniques have evolved and proven accuracy, compliance can more and more be shown by sufficiently validated nume cal analyses. This study shows such an example f successful simulative demonstration of bird strike resistance of a searchlight and its pod as ext rnal equipment of a military helicopter. The finite lement model was built up and validated step by step according t the building block approach from coupon level up to the full-scale structural level. The focus was on the accurate non-linear constitutive modeling of the different aluminum alloys and mechanical fasteners of the target structure. The searchlight pod as well as its internal electrical components and attachments were modelled with a high level of detail in order to allow for accurate results evaluations. A validated smoothed particle hydrodynamics (SPH) bird impactor model was used to simulate different load cases and impact positions of this fluid-structure interaction scenario with a water-like soft body projectile. Although plastic deformations and partial fracture of the outer housings of the structure were observed, no critical failure mode, detachment of critical parts or loss of structural integrity occurred. These analyses were accepted by the authorities as means of compliance and demonstrate today’s progress in airwort hiness certification by simulation. © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ICSI 2017. © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ICSI 2017 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. © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. Abstract

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

* Corresponding author. Tel.: +49-89-607-25884; fax: +49-89-607-23067. E-mail address: sebastian.heimbs@airbus.com

2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. 2452-3216  2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ICSI 2017 10.1016/j.prostr.2017.07.044 * Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt 2452-3216 © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ICSI 2017. 2452-3216 © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ICSI 2017. * Corresponding author. Tel.: +49-89-607-25884; fax: +49-89-607-23067. E-mail address: sebastian.heimbs@airbus.com