1. The information contained in this document is Volvo Aero Corporation Proprietary Information and it shall not – either in its original or in any modified form, in whole or in part – be reproduced, disclosed to a third party, or used for any purpose other than that for which it is supplied, without the written consent of Volvo Aero Corporation. Any infringement of these conditions will be liable to legal action. TURBO POWER, Compressors

2. 10110 Utg. 4 Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. 7161, Hans Mårtensson 10110 Utg. 10 TurboPower : Compressors 2008-04-10, Slide 2 Session Hans Mårtensson, VAC, Compressor development with emphasis on aeromechanics Johan Forsman, VAC, Assessment of an compressor vibration issue. Damian Vogt, KTH, The TurboVib Project Ronnie Bladh, Siemens, Mistuning and modern assessment methods

3. 10110 Utg. 4 Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. 7161, Hans Mårtensson 10110 Utg. 10 TurboPower : Compressors 2008-04-10, Slide 3 On-going Compressor development within VAC Hulda - FoT25 demonstration of technology for a year 2020 engine design Pressure ratio 7 over 2 stages VITAL Booster – A very highly loaded IPC for reduced weight and high efficiency EU programme 5 stages to replace 9 stages Fan demonstrator – Full scale demonstration increased performance fan 20% increased power in the same engine envelope Film

4. 10110 Utg. 4 Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. 7161, Hans Mårtensson 10110 Utg. 10 TurboPower : Compressors 2008-04-10, Slide 4 Design process - Blades Performance Well matched components Optimized 3D aerodynamic design Operability Satisfactory stall margin capability Vibration Minimal risk for high amplitude forced response Safe flutter margins Life Limited stresses Analytical prediction, design and verification of all requirements is the governing philosophy

5. 10110 Utg. 4 Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. 7161, Hans Mårtensson 10110 Utg. 10 TurboPower : Compressors 2008-04-10, Slide 5 Performance - steps taken Performance improvements is the primary driver of the product Robustness and reliability issues are starting to be requested using CFD 3D multi stage CFD is today a standard tool for analysis Accuracy on global performance is good Off-design performance is difficult Assessment of operability issues, distortion etc. still out of reach in design Detailed compressor tests serve to calibrate

6. 10110 Utg. 4 Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. 7161, Hans Mårtensson 10110 Utg. 10 TurboPower : Compressors 2008-04-10, Slide 6 Hulda characteristics Fan data: Rotor tip diameter: 400 mm Rotor tip speed: 440 m/s @ 21000 rpm (Aluminum blisk) Hub/Tip radius ratio (inlet): 0.41 Mass flow: 20 kg/s PR_TT: 2.1 Goal Performance demonstration Validation and calibration of computational tools Commissioning of rig Mechanically conservative blading Conservative profiles for aerodynamics

7. 10110 Utg. 4 Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. 7161, Hans Mårtensson 10110 Utg. 10 TurboPower : Compressors 2008-04-10, Slide 7 Boundary Conditions Initial 2D profiles at 3 span pos. Meanline definition (Excel spread sheet tool / Experience based correlations) Optimized 2D profiles Volblade Blade Generation Grid Generation & quasi-3D CFD Volblade Blade Generation Grid Generation & 3D CFD 3D optimization 2D optimization Grid Generation & Stress + Modal Analyses Matlab optimization platform Stage Analysis & Performance eval. (CFD) Initial 3D blade

8. 10110 Utg. 4 Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. 7161, Hans Mårtensson 10110 Utg. 10 TurboPower : Compressors 2008-04-10, Slide 8 Optimization method for Hulda 3D 1- point combined structural and aerodynamic optimization introduced in Hulda 1½ stage design Very high pressure ratios are demonstrated at good efficiency ASME papers published on method Tests have started, interrupted on bearing failure

9. 10110 Utg. 4 Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. 7161, Hans Mårtensson 10110 Utg. 10 TurboPower : Compressors 2008-04-10, Slide 9 Calculated performance Compressor maps with nominal vane setting Relatively coarse grid. Tip leakage not included. Entropy contours from resolving the tip clearance. Total pressure contours of the flow coming out from stator 1. Vortex rolling up at bottom Whereas the more detailed CFD analyses show that there are further optimization to be done, the performance that is estimated is quite close to the goals. As experimental data appear the CFD data will be further explored

10. 10110 Utg. 4 Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. 7161, Hans Mårtensson 10110 Utg. 10 TurboPower : Compressors 2008-04-10, Slide 10 Blading for VITAL 2 point optimization ADP+stall introduced 3½ stage design Less conservative blading Thinner profiles (t/c) Trailing edge curls (R2) Forward sweep (R1) High efficiency targets

11. 10110 Utg. 4 Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. 7161, Hans Mårtensson 10110 Utg. 10 TurboPower : Compressors 2008-04-10, Slide 11 Aeromechanic analysis in design

12. 10110 Utg. 4 Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. 7161, Hans Mårtensson 10110 Utg. 10 TurboPower : Compressors 2008-04-10, Slide 12 Flutter assessment using CFD Tuned analysis of single mode flutter Single blade row SS PS Local unsteady pressure coefficients on suction side (SS) and pressure side (PS) at operating point N90 high and IBPA -90deg S-curves showing aerodynamic damping for all nodal diameters on 2F and 1T modes

13. 10110 Utg. 4 Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. 7161, Hans Mårtensson 10110 Utg. 10 TurboPower : Compressors 2008-04-10, Slide 13 N100 0.8*N100 0.6*N100 1.07*N105 1F 1T 2F Crossing rules for design against resonances: Campbell Diagram for the Rotor

14. 10110 Utg. 4 Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. 7161, Hans Mårtensson 10110 Utg. 10 TurboPower : Compressors 2008-04-10, Slide 14 Forced response calculation using CFD Animation Limit of what can be done on computer Used in verification Delivering huge amounts ~1TB data Rational safe methods for post processing needed

15. 10110 Utg. 4 Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. 7161, Hans Mårtensson 10110 Utg. 10 TurboPower : Compressors 2008-04-10, Slide 15 Conclusion Integrated tools will provide safer products Reliability and understanding of accuracy is capital to improving aeromechanical assessment Less conservative methods will allow more efficient compressors

16. 10110 Utg. 4 Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. 7161, Hans Mårtensson 10110 Utg. 10 TurboPower : Compressors 2008-04-10, Slide 16 Example