Investigations of rotating instability and fluctuating tip clearance flow in a low-speed axial compressor

Abstract

To investigate the relationship between rotating instability and fluctuating tip clearance flow, experimental tests as well as numerical studies are conducted on a 1.5 stage low-speed axial compressor rig. The rotating instability is detected through casing mounted dynamic pressure sensors. The phase-locked and root-mean-square pressure contours show that the interaction of tip clearance flow with the neighboring blade is the most likely cause of casing flow field fluctuation. From the calculated results of entire-annulus cascade, it is found that the tip clearance vortex structures oscillate periodically at low flow rate conditions. That leads to intense fluctuation of the casing flow field. Further, phase lag of pressure fluctuations exists between two neighboring passages, which induces a rotating pressure pattern of multiple frequencies. The frequency characteristics of this rotating pressure pattern caused by fluctuating tip clearance flow is coincident with the frequency of rotating instability. This suggests that the fluctuating tip clearance flow is the major contributor to the initiation of rotating instability.

Keywords

Rotating instability fluctuating tip clearance flow unsteady pressure measurements numerical computational fluid dynamics simulations frequency characteristics

Get full access to this article

View all access options for this article.

References

Mathioudakis K and Breugelmans FAE. Development of small rotating stall in a single stage axial compressor. 1985, ASME paper 85-GT-227.

Baumgartner M, Kameier F and Hormouziadis J. Non engine order blade vibration in a high speed compressor. In: Twelfth international symposium on airbreathing engines, ISABE 95-7094, Melbourne, Australia, 1995.

Kameier

Neise

. Rotating blade flow instability as a source of noise in axial turbomachines. J Sound Vib 1997; 203: 833–853.

Kameier

Neise

. Experimental study of tip clearance losses and noise in axial turbomachines and their reduction. J Turbomach 1997; 119: 460–471.

Marz

Hah

Neise

. An experimental and numerical investigation into the mechanisms of rotating instability. J Turbomach 2002; 124: 367–374.

Mailach

Lehmann

Vogeler

. Rotating instabilities in an axial compressor originating from the fluctuating blade tip vortex. J Turbomach 2001; 123: 453–460.

Hah C, Bergner J and Schiffer H-P. Tip clearance vortex oscillation, vortex shedding and rotating instability in an axial transonic compressor rotor. In: ASME turbo expo 2008, Berlin, Germany, GT2008-50105, 2008.

Hah C, Voges M, Mueller MW, et al. Characteristics of tip clearance flow instability in a transonic compressor. In: ASME turbo expo 2010, Glasgow, UK, GT2010-22101, 2010.

. Role of tip clearance flow in rotating instabilities and nonsynchronous vibrations. J Propul Power 2010; 26: 556–561.

10.

Thomassin

Mureithi

. The tip clearance flow resonance behind axial compressor nonsynchronous vibration. J Turbomach 2011; 133: 041030–041030.

11.

Pardowitz B, Tapken U and Enghardt L. Time-resolved rotating instability waves in an annular cascade. In: 18th AIAA/CEAS aeroacoustics conference, Colorado Springs, CO, AIAA 2012-2132, 2012.

12.

Zhang

Stuer

. A numerical investigation of rotating instability in steam turbine last stage. J Turbomach 2013; 135: 011009–1–011009-9.

13.

Lin

Zhang

. Numerical investigation on the self-induced unsteadiness in tip clearance flow for a transonic fan rotor. ASME J Turbomach 2010; 132: 021017–021017.

14.

Taghavi-Zenouz

Eslami

. Numerical simulation of unsteady tip clearance flow in an isolated axial compressor rotor blades row. Proc IMechE, Part C: J Mechanical Engineering Science 2012; 226: 82–93.

15.

Tian

. Investigation of pre-stall behavior in an axial compressor rotor—Part I: Unsteadiness of tip clearance flow. J Turbomach 2012; 134: 051027–051027.

16.

Tyler

Sofrin

. Axial flow compressor noise studies. SAE Trans 1962; 70: 309–332.