RollsRoyce UTC Aero System Design Integration Performance Turbine

Rolls-Royce UTC Aero System Design, Integration & Performance Turbine Over-speed Aerodynamics Academic Supervisor: V. Pachidis Industrial Supervisor: S. Brown, A. Rowe RAe. S Annual Lecture Competition, Cranfield, 14 th July 2016 Image Courtesy of Rolls-Royce plc David John R © 2016 Cranfield University, School of Aerospace, Transport & Manufacturing, Propulsion Engineering Centre The information presented here is the property of the Cranfield University Rolls-Royce UTC in Gas Turbine Performance Engineering and may not be copied or communicated to a third party, or used for any purpose other than that for which it is supplied without the express written consent of Cranfield University and Rolls-Royce plc.

Rolls-Royce UTC Aero System Design, Integration & Performance Overview Ø Engine Over-speed Event Ø Turbine Behaviour Ø Hi-fidelity, Event based Characterization Ø Methodology Ø Axial Displacement & Secondary Air System Ø Damage to Rotor Shroud tip as design modification Ø Flow Physics Ø Implementation in Model Ø Conclusion Cranfield, 14 of April July 2016 Cranfield, 7 th of 2016 th 2

Rolls-Royce UTC Aero System Design, Integration & Performance Engine Over-speed Event Qantas A 380 Flight 32 – 4 th November 2010 Shaft Over-speed Failure [1] ATSB Report dated June 2013 on Qantas Flight 32 Incident on November 2010 Cranfield, 14 th of July 2016 Cranfield, 7 of April 2016 th 3

Rolls-Royce UTC Aero System Design, Integration & Performance Engine Over-speed Event • Compressor reverse flow, stall, possible surge • Secondary air system behaviour • Turbine displacement and entanglement Cranfield, 14 th of July 2016 Cranfield, 7 th of April 2016 • Decoupling • Turbine rapid acceleration 4

Rolls-Royce UTC Aero System Design, Integration & Performance Engine Over-speed Event – Modelling • High Pressure Spool Failure Engine Over-speed Model • Predict Speed of Rotor with time after shaft failure Cranfield, 14 th of July 2016 Cranfield, 7 of April 2016 th 5

Rolls-Royce UTC Aero System Design, Integration & Performance Turbine Solver in Over-speed model • HP Rotor airfoil Torque • HP Turbine Mass Flow Function • IP Turbine Mass Flow Function f • Speed function • Pressure Ratio • Typically carried out for clean configuration • Scaling factors used for tip clearance - ~ 1% Cranfield, 14 th of July 2016 Cranfield, 7 of April 2016 th 6

Rolls-Royce UTC Aero System Design, Integration & Performance Hi Fidelity Event based Characterisation • Axial displacement of shrouded rotors • Modelling of Rim and Tip Seal • Secondary Flows from rim seals Cranfield, 14 of April July 2016 Cranfield, 7 th of 2016 th 7

Rolls-Royce UTC Aero System Design, Integration & Performance Axial Displacement • Thermo-mechanical Friction model • Contact and Wear • Developed from non-linear structural dynamic analyses [2] Psarra, A. , Pachidis, V. and Pilidis, P. , 2009, January. Finite Element Turbine Blade Tangling Modelling Following a Shaft Failure. In ASME Turbo Expo 2009: Power for Land, Sea, and Air (pp. 73 -81). American Society of Mechanical Engineers. [3] Gonzalez, A. and Pachidis, V. , 2014, June. On the Numerical Simulation of Turbine Blade Tangling After a Shaft Failure. In ASME Turbo Expo 2014: Turbine Technical Conference and Exposition (pp. V 07 BT 33 A 026 -V 07 BT 33 A 026). American Society of Mechanical Engineers. Cranfield, 14 th of July 2016 Cranfield, 7 of April 2016 th 8

Rolls-Royce UTC Aero System Design, Integration & Performance Axial Displacement Cranfield, 14 of July 2016 Cranfield, 7 th of April 2016 th 9

Rolls-Royce UTC Aero System Design, Integration & Performance Flow Path Change 0 mm Cranfield, 14 th of July 2016 Cranfield, 7 of April 2016 th 10 mm 15 mm 10

Rolls-Royce UTC Aero System Design, Integration & Performance SAS network • Validated Transient Model • Heat transfer effects • Sinks, Sources, Links [4] Gallar, L. , Calcagni, C. , Pachidis, V. and Pilidis, P. , 2009, January. Development of a One-Dimensional Dynamic Gas Turbine Secondary Air System Model—Part I: Tool Components Development and Validation. In ASME Turbo Expo 2009: Power for Land, Sea, and Air (pp. 457 -465). American Society of Mechanical Engineers. [5] Calcagni, C. , Gallar, L. and Pachidis, V. , 2009, January. Development of a One-Dimensional Dynamic Gas Turbine Secondary Air System Model—Part II: Assembly and Validation of a Complete Network. In ASME Turbo Expo 2009: Power for Land, Sea, and Air (pp. 435 -443). American Society of Mechanical Engineers. Cranfield, 14 th of July 2016 Cranfield, 7 of April 2016 th 11

Rolls-Royce UTC Aero System Design, Integration & Performance Flow Property Change Cranfield, 14 th of July 2016 Cranfield, 7 of April 2016 th 12

Rolls-Royce UTC Aero System Design, Integration & Performance 3 D RANS Study – HP Turbine Cranfield, 14 th of July 2016 Cranfield, 7 of April 2016 th 13

Rolls-Royce UTC Aero System Design, Integration & Performance 3 D RANS Characterisation – HP Turbine Cranfield, 14 th of July 2016 Cranfield, 7 of April 2016 th 14

Rolls-Royce UTC Aero System Design, Integration & Performance Aerodynamic Analyses at different displacements Cranfield, 14 th of July 2016 Cranfield, 7 of April 2016 th Grid Convergence Studies 15

Rolls-Royce UTC Aero System Design, Integration & Performance Flow Physics Cranfield, 14 th of July 2016 Cranfield, 7 of April 2016 th 16

Rolls-Royce UTC Aero System Design, Integration & Performance Flow Physics Cranfield, 14 th of July 2016 Cranfield, 7 of April 2016 th 17

Rolls-Royce UTC Aero System Design, Integration & Performance Flow Physics Cranfield, 14 th of July 2016 Cranfield, 7 th of April 2016 18

Rolls-Royce UTC Aero System Design, Integration & Performance Change in Parameters [6] L Pawsey, D John, V Pachidis, 2016, June. Turbine Overspeed- On the Aerodynamic Performance of an Unlocated HP Turbine Rotor. Manuscript submitted to XXIII International Symposium on Air Breathing Engines, Manchester, England Cranfield, 14 th of July 2016 Cranfield, 7 th of April 2016 19

Rolls-Royce UTC Aero System Design, Integration & Performance Implementation in Model • Improved accuracy in prediction with implementation of displacement characteristics Cranfield, 14 th of July 2016 Cranfield, 7 th of April 2016 20

Rolls-Royce UTC Aero System Design, Integration & Performance Engine Over-speed Event – Modelling • Certification • EASA – ‘Hazardous Engine Effects’ – Free Running Turbine Over-speed • Acceptable Means of Compliance E 850 • Analyses based in service / test experience • Certification Memorandum – More reliable Analytical Models to predict shaft failure event [6] L Pawsey, D John, V Pachidis, 2016, June. Turbine Overspeed- On the Aerodynamic Performance of an Unlocated HP Turbine Rotor. Manuscript submitted to XXIII International Symposium on Air Breathing Engines, Manchester, England [7] Certification specifications for engines CS-E - Amendment 3. Technical report, European Aviation Safety Agency, 2010 [8] Certification memorandum - turbine over-speed resulting from shaft failure. Technical report, European Aviation Safety Agency, 2012 Cranfield, 14 th of July 2016 Cranfield, 7 of April 2016 th 21

Rolls-Royce UTC Aero System Design, Integration & Performance Damage to Rotor Shroud tip 0 mm 15 mm • Trigger Unbalance after shaft failure • Contact between Rotor Tip & Casing Cranfield, 14 th of July 2016 Cranfield, 7 of April 2016 th 22

Rolls-Royce UTC Aero System Design, Integration & Performance Aerodynamic Analyses with Damaged Tip Cranfield, 14 th of July 2016 Cranfield, 7 th of April 2016 23

Rolls-Royce UTC Aero System Design, Integration & Performance Flow Physics Cranfield, 14 th of July 2016 Cranfield, 7 th of April 2016 24

Rolls-Royce UTC Aero System Design, Integration & Performance Flow Physics Cranfield, 14 th of July 2016 Cranfield, 7 th of April 2016 25

Rolls-Royce UTC Aero System Design, Integration & Performance Flow Physics Cranfield, 14 th of July 2016 Cranfield, 7 th of April 2016 26

Rolls-Royce UTC Aero System Design, Integration & Performance Change in Parameters Cranfield, 14 th of July 2016 Cranfield, 7 th of April 2016 27

Rolls-Royce UTC Aero System Design, Integration & Performance Implementation in Model • Reduction in terminal speed with damaged shroud tip Cranfield, 14 th of July 2016 Cranfield, 7 th of April 2016 28

Rolls-Royce UTC Aero System Design, Integration & Performance Engine Over-speed Event – Modelling • Design of Turbine Rotor Sub-assemblies • Over-speed and Burst margins • Sizing of Rotor Disks • Reduction in Overall Weight of System • Improved T/W ratio and Specific Fuel Consumption [9] L Pawsey, D John, V Pachidis, 2016, July. Turbine Overspeed- On the Aerodynamic Performance of an Unlocated HP Turbine Rotor with Worn Seals. Manuscript under review. Cranfield, 14 th of July 2016 Cranfield, 7 of April 2016 th 29

Rolls-Royce UTC Aero System Design, Integration & Performance Conclusion • Integrated Structural, Secondary Air System and Aerodynamic Methodology • Hi-Fidelity Event based Characterisation of Turbines • Greatly improved accuracy in terminal speed prediction Ease of certification • Use of analyses methodology to explore design variants to reduce terminal speed of rotor - Carry over benefits to design Cranfield, 14 th of July 2016 Cranfield, 7 th of April 2016 30