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Submitted
August 2, 2023
Published
August 2, 2023
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Abstract

Two critical aspects of the casing wall flow structure in a subsonic axial flow compressor are studied in this paper: flow mechanism leading to stalling at different stagger angle configurations; and the effect of tip leakage flows on these flow phenomena. In some of the previous works, casing wall flow instabilities similar to the ones discussed in the present paper were reported, typically for high stagger angle rotor designs. However under what conditions flow tends to take such shapes were not discussed in detail. This work attempts to address this through a detailed numerical study on unswept and forward swept rotors, for different stagger angle settings, and for varied levels of rotor tip gaps. Three candidate rotors (unswept, 20° true swept, 20° axially swept) are studied with three tip clearances (0.0%, 0.7%, and 2.7% of the blade chord) for three stagger angle changes (0°, +3° and +5°). Stagger angle is found to have significant effect on suction surface flow separations. Tip clearance is observed to be critical on the inception of casing wall flow instabilities, especially at higher stagger angles. Hub endwall flow structure and the downstream flow evolution are also discussed in the paper.

Keywords

Stagger angle, Tip clearance, Blade sweep, Flow separation, Total and static pressure coefficients, Axial velocity coefficient

Article Details

How to Cite
Ramakrishna, P., & Govardhan, M. (2023). Inception of Casing Wall Flow Instabilities and Downstream Flow Evolution in Subsonic Axial Compressor Rotors At High Rotor Stagger Angles. Journal of Aerospace Sciences and Technologies, 66(2), 106–126. https://doi.org/10.61653/joast.v66i2.2014.447
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References

  1. Ramakrishna, P. V. and Govardhan, M., "Combined Effects of Forward Sweep and Tip Clearance on the Performance of Axial Flow Compressor Stage", Proceedings of the ASME Turbo Expo, Orlando, Fla, USA, GT2009-59840, 2009.
  2. Ramakrishna, P. V. and Govardhan, M., "Study of Sweep and Induced Dihedral Effects in Subsonic Axial Flow Compressor Passages - Part II: Detailed Study of the Effects on Tip Leakage Phenomena", International Journal of Rotating Machinery, Vol.2010, Article ID 491413, 13 Pages, 2010.
  3. Yoon, Y.S., Song, S. J. and Shin, H. W., "Influence of Flow Coefficient, Stagger Angle, and Tip Clearance on Tip Vortex in Axial Compressors," Journal of Fluids Engineering, Vol.128, No.6, pp.1274-1280, 2006.
  4. Ramakrishna, P.V. and Govardhan, M., "Effect of Tip Clearance on the Performance of Forward Swept Subsonic Axial Compressor Rotors at High Stagger Angles", Proceedings of the ASME International Mechanical Engineering Congress and Exposition (IMECE2011), Denver, Colorado, USA, IMECE2011 - 65103, 2011.
  5. März, J., Hah, C. and Neise, W., "An Experimental and Numerical Investigation into the Mechanisms of Rotating Instability", ASME Journal of Turbomachinery, Vol.124, No.3, pp.367-375, 2002.
  6. Mailach, R., Lehmann, I. and Vogeler, K., "Rotating Instabilities in an Axial Compressor Originating from the Fluctuating Blade Tip Vortex", ASME Journal of Turbomachinery, Vol.123, pp.453-463, 2001.
  7. Zierke, W.C., Farrell, K.J. and Straka, W.A., "Measurement of the Tip Clearance Flow for a High- Reynolds-Number Axial-flow Rotor", ASME Journal of Turbomachinery, Vol.117, pp.522-532, 1995.
  8. Hoying, D.A., Tan, C.S.., Vo, H.D. and Greitzer, E.M., "Role of Blade Passage Flow Structures in Axial Compressor Rotating Stall Inception", ASME Journal of Turbomachinery, Vol.121, pp.735-742, 1999.
  9. Wisler, D.C., "Core Compressor Exit Stage Study, Volume IV - Data and Performance Report for the Best Stage Configuration, NASA CR-165357, 1981.
  10. Silkowski, P.D., "Measurements of Rotor Stalling in a Matched and a Mismatched Multistage Compressor", GTL Report, 221, Gas Turbine Laboratory, Massachusetts Institute of Technology, 1995.
  11. Davis, R.L. and Yao, J., "Axial Compressor Rotor Flow Structure at Stall-inception", Proceedings of AIAA Aerospace Sciences Meeting and Exhibit, AIAA 2006-419, 2006.
  12. Suder, K.L. and Celestina, M.L., "Experimental and Computational Investigation of the Tip Clearance Flow in a Transonic Axial Compressor Rotor", NASA Technical Memorandum, TM-106711, 1994.
  13. Saathof, H., Deppe, A. and Stark, U., "Steady and Unsteady Casing Wall Flow Phenomena in a Single- Stage Low-Speed Compressor at Part-Load Conditions", International Journal of Rotating Machinery, No.9, pp.327-335, 2003.
  14. Cumpsty, N.A., "Part-Circumference Casing Treatment and the Effect on Compressor Stall", ASME Paper No. 89-GT-312, 1989.
  15. Day, I.J., "Stall Inception in Axial Flow Compressors", ASME Journal of Turbomachinery, No.115, pp.1-9, 1993.
  16. Saathoff, H. and Stark, U., "Tip Clearance Flow iNduced Endwall Boundary Layer Separation in a Single-stage Axial-flow Low-speed Compressor", ASME Paper, 2000-GT-0501, 2000.
  17. Ramakrishna, P. V. and Govardhan, M., "Study of Sweep and Induced Dihedral Effects in Subsonic Axial Flow Compressor Passages - Part I: Design Considerations - Changes in Incidence, Deflection, and Streamline Curvature", International Journal of Rotating Machinery, Vol.2009, Article ID 787145, 11 Pages, 2009.
  18. Ramakrishna, P.V. and Govardhan, M., "Aerodynamic Performance of Low Speed Axial Flow Compressor Rotors with Sweep and Tip Clearance", Journal of Engineering Applications of Computa- tional Fluid Mechanics, Vol.3, No.2, pp.195-206, 2009.
  19. Ramakrishna, P.V., "Computational Studies on Sweep, Tip Clearance and Stagger Angle Effects in a Subsonic Axial Flow Compressor", Ph.D. Dissertation, Indian Institute of Technology Madras, Chennai, 2011.
  20. Krishnakumar, O.G., "Experimental and Computational Studies on Forward Swept Axial Compressor Rotors", M.S. Dissertation, Indian Institute of Technology Madras, Chennai, 2003.