Research Papers

Consequences of Borescope Blending Repairs on Modern High Pressure Compressor Blisk Aeroelasticity

[+] Author and Article Information
Benjamin Hanschke

Chair of Structural Mechanics and
Vehicle Vibration Technology,
Brandenburg University of Technology
Cottbus D-03046, Germany
e-mail: benjamin.hanschke@b-tu.de

Arnold Kühhorn

Chair of Structural Mechanics and
Vehicle Vibration Technology,
Brandenburg University of Technology
Cottbus D-03046, Germany

Sven Schrape, Thomas Giersch

Rolls-Royce Deutschland Ltd & Co KG,
Blankenfelde-Mahlow D-15827, Germany

1Corresponding author.

Manuscript received February 14, 2018; final manuscript received September 21, 2018; published online January 16, 2019. Assoc. Editor: Coutier-Delgosha Olivier.

J. Turbomach 141(2), 021002 (Jan 16, 2019) (7 pages) Paper No: TURBO-18-1028; doi: 10.1115/1.4041672 History: Received February 14, 2018; Revised September 21, 2018

Objective of this paper is to analyze the consequences of borescope blending repairs on the aeroelastic behavior of a modern high pressure compressor (HPC) blisk. To investigate the blending consequences in terms of aerodynamic damping and forcing changes, a generic blending of a rotor blade is modeled. Steady-state flow parameters like total pressure ratio, polytropic efficiency, and the loss coefficient are compared. Furthermore, aerodynamic damping is computed utilizing the aerodynamic influence coefficient (AIC) approach for both geometries. Results are confirmed by single passage flutter (SPF) simulations for specific interblade phase angles (IBPA) of interest. Finally, a unidirectional forced response analysis for the nominal and the blended rotor is conducted to determine the aerodynamic force exciting the blade motion. The frequency content as well as the forcing amplitudes is obtained from Fourier transformation of the forcing signal. As a result of the present analysis, the change of the blade vibration amplitude is computed.

Copyright © 2019 by ASME
Your Session has timed out. Please sign back in to continue.


Jones, L. C. , and Litzenberg, H. , 2013, “ A Method of Inspecting and/or Repairing Component and a Device for Inspecting and/or Repairing a Component,” UK Patent No. 2474834B.
Adair, T. L. , Owens, J. L. , Grady, G. , Winter, H. I. , and Grant, R. C. , 1998, “ Blending Borescope Inspection (BBI) Maintenance Service Equates to Cost Savings,” AUTOTESTCON IEEE Systems Readiness Technology Conference, Salt Lake City, UT, Aug. 25–27, pp. 486–493.
Tang, W. , Epureanu, B. I. , and Filippi, S. , 2017, “ Models for Blisks With Large Blends and Small Mistuning,” Mech. Syst. Signal Process., 87, pp. 161–179. [CrossRef]
Chen, G. , and Hou, J. , 2015, “ Effects of Mistuning Patterns on Forced Response for an Integrally Bladed Disk,” Recent Advances in Structural Integrity Analysis (Proceedings of the International Congress), Woodhead Publishing, Cambridge, UK.
Karger, K. , and Bestle, D. , 2014, “ Parametric Blending and FE-Optimisation of a Compressor Blisk Test Case,” Advances in Evolutionary and Deterministic Methods for Design, Optimization and Control in Engineering and Sciences (Computational Methods in Applied Sciences, Vol. 36), D. Greiner, B. Galván, J. Périaux, N. Gauger, K. Giannakoglou, and G. Winter, eds., Springer, Cham, Switzerland.
Sayma, A. I. , Vahdati, M. , Sbardella, L. , and Imregun, M. , 2000, “ Modeling of Three-Dimensional Viscous Compressible Turbomachinery Flows Using Unstructured Hybrid Grids,” AIAA J., 38(6), pp. 945–954. [CrossRef]
Sayma, A. I. , Vahdati, M. , and Imregun, M. , 2000, “ An Integrated Nonlinear Approach for Turbomachinery Forced Response Prediction—Part I: Formulation,” J. Fluids Struct., 14(1), pp. 87–101. [CrossRef]
Vahdati, M. , Sayma, A. I. , and Imregun, M. , 2000, “ An Integrated Nonlinear Approach for Turbomachinery Forced Response Prediction—Part II: Case Studies,” J. Fluids Struct., 14(1), pp. 103–125. [CrossRef]
Stelldinger, M. , Giersch, T. , Figaschewsky, F. , and Kühhorn, A. , 2016, “ A Semi-Unstructured Turbomachinery Meshing Library With Focus on Modeling of Specific Geometrical Features,” European Congress on Computational Methods in Applied Sciences and Engineering, Crete Island, Greece, June 5–10, pp. 384–401. https://www.eccomas2016.org/proceedings/pdf/7554.pdf
Crawley, E. F. , 1988, “ Aeroelastic Formulation for Tuned and Mistuned Rotors,” Advisory Group for Aerospace Research and Development, Neuilly sur Seine, France, Paper No. 19.
Nipkau, J. , 2011, “ Analysis of Mistuned Blisk Vibrations Using a Surrogate Lumped Mass Model With Aerodynamic Influences,” Ph.D. thesis, Brandenburgisch Technische Universität Cottbus, Senftenberg, Germany.
Vahdati, M. , Sayma, A. I. , Marshall, J. G. , and Imregun, M. , 2001, “ Mechanisms and Prediction Methods for Fan Blade Stall Flutter,” J. Propul. Power, 17(5), pp. 1100–1108. [CrossRef]
Carta, F. O. , 1967, “ Coupled Blade-Disk-Shroud Flutter Instabilities in Turbojet Engine Rotors,” J. Eng. Power, 89(3), pp. 419–426.
Hanamura, Y. , Tanaka, H. , and Yamaguchi, K. , 1980, “ A Simplified Method to Measure Unsteady Forces Acting on the Vibrating Blades in Cascade,” Bull. JSME, 23(180), pp. 880–887. [CrossRef]
Stapelfeldt, S. , 2014, “ Advanced Methods for Multi-Row Forced Response and Flutter Computations,” Ph.D. thesis, Imperial College London, London. https://spiral.imperial.ac.uk/bitstream/10044/1/24824/1/Stapelfeldt-SC-2014-PhD-Thesis.pdf
Figaschewsky, F. , Kühhorn, A. , Beirow, B. , Giersch, T. , Nipkau, J. , and Meinl, F. , “ Simplified Estimation of Aerodynamic Damping for Bladed Rotors—Part 2: Experimental Validation During Operation,” ASME Paper No. GT2016-56458.


Grahic Jump Location
Fig. 2

Comparison of nominal and blended geometry CFD mesh

Grahic Jump Location
Fig. 1

Comparison of the displacement magnitude of the nominal and blended mode shapes

Grahic Jump Location
Fig. 3

Relative outlet flow angle

Grahic Jump Location
Fig. 4

Velocity field at blending position

Grahic Jump Location
Fig. 5

Relative static pressure of nominal geometry and blending repaired blade

Grahic Jump Location
Fig. 6

Aerodynamic damping curves

Grahic Jump Location
Fig. 7

Work done by aerodynamic forces for interblade phase angle of −102 deg at blade pressure side

Grahic Jump Location
Fig. 8

Work done by aerodynamic forces for interblade phase angle of −102 deg at blade suction side

Grahic Jump Location
Fig. 9

Line spectra of modal forcing

Grahic Jump Location
Fig. 10

Maximum local aerodynamic force comparison for blade pressure side

Grahic Jump Location
Fig. 11

Maximum local aerodynamic force comparison for blade suction side



Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In