Unsteady Flow and Whirl-Inducing Forces in Axial-Flow Compressors: Part I—Experiment

[+] Author and Article Information
A. F. Storace, D. C. Wisler, H.-W. Shin, B. F. Beacher

GE Aircraft Engines Cincinnati, OH 45215

F. F. Ehrich, Z. S. Spakovszky, M. Martinez-Sanchez

Massachusetts Institute of Technology, Cambridge, MA

S. J. Song

Seoul National University, Seoul, Korea

J. Turbomach 123(3), 433-445 (Feb 01, 2000) (13 pages) doi:10.1115/1.1378299 History: Received February 01, 2000
Copyright © 2001 by ASME
Your Session has timed out. Please sign back in to continue.



Grahic Jump Location
Models of whirl-inducing forces in turbines and compressors. Net force Fx=Fm+Fu acts perpendicular to the axis of displacement and drives rotor whirl; see Appendix B1.
Grahic Jump Location
Schematic showing cross section of compressor A blading
Grahic Jump Location
LSRC configuration for centerline offset tests showing circumferential variation in rotor tip clearance εR, and stator shroud seal clearance, εs. Looking down on spinning, nonwhirling eccentric rotor with casings moved relative to rotor assembly; see Appendix B2.
Grahic Jump Location
Typical example showing the circumferential variation in unsteady static pressure obtained from a Kulite pressure transducer embedded in a rotor airfoil (96 percent span and 50 percent chord for the large rotor offset): (a) raw data, (b) FFT of raw data, (c) filtered signal.
Grahic Jump Location
The two coordinate systems used to resolve blade forces: (1) blade fixed coordinate (Ttan,R), (blade geometry defined in this system); (2) rotating coordinate (X,Y) (the blade azimuth angle θ is defined in this coordinate system); see Appendix B3
Grahic Jump Location
Overall performance of compressor A showing the effects of variation in axisymmetric clearances relative to baseline performance. Compressors A1–A4 are defined in Table 3 of Appendix A. Data accuracy is identical to that for Fig. 7, therefore data symbols are removed for clarity.
Grahic Jump Location
Overall performance of Compressor A for rotor centerline offset tests relative to baseline performance
Grahic Jump Location
Performance derivatives for compressor A in terms of change in total average clearance from baseline clearance levels
Grahic Jump Location
Performance characteristic for compressors B and C
Grahic Jump Location
(a, b, c) Contours of unsteady static pressure difference on the rotor airfoils at three clearance levels around the circumference for the large centerline offset. Zone A is affected by variation in rotor blade tip clearance and zone B is affected by stator shroud seal clearance. Both zones are affected by any radial flow redistribution; (d) chordwise distribution of measured, steady-state static pressure on rotor airfoil at 80 percent span.
Grahic Jump Location
Circumferential variation of stator airfoil loading for Compressor A showing the effects different levels of rotor tip clearance due to centerline offset. (a–c) 90 percent span; (d–f) 50 percent span; (g–i) 5 percent span. Low, medium, and high compressor loading were obtained at test points 1, 3, and 5, respectively, in Fig. 7.
Grahic Jump Location
Circumferential variation of the unsteady whirl inducing force components and running rotor tip clearance for the large centerline offset of LSRC Compressor A. Zone 1 is for net force increased and zone 2 for net force decreased. Data shown for Test Point 5 in Fig. 7; see Appendix B3a.
Grahic Jump Location
Distribution of tangential blade force for LSRC Offset Rotor Test showing direction of mean and unsteady forces (Fm and Fu) at various circumferential positions; see Appendices B1 and B3a
Grahic Jump Location
Regression plot of cross-axis-force for high compressor loading test point 5 in Fig. 7
Grahic Jump Location
Computed beta coefficients for the LSRC compressor A offset rotor test showing that unsteady forces promote backward whirl over most of the compressor operating range. Test Points 1–6 correspond to those in Fig. 7.




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