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Type of Document Dissertation Author Cameron, Joshua David Author's Email Address jcamero1@nd.edu URN etd-12152006-152024 Title Stall Inception in a High-Speed Axial Compressor Degree Doctor of Philosophy Department Aerospace and Mechanical Engineering Advisory Committee
Advisor Name Title Tracy L. Kijewski-Correa Committee Chair Charles Gendrich Committee Member Eric Jumper Committee Member Scott C. Morris Committee Member Thomas Corke Committee Member Keywords
- Aerospace
- Gas Turbines
- Stall Inception
- Rotating Stall
- Axial Compressors
Date of Defense 2006-12-06 Availability unrestricted Abstract A research program designed to provide understanding of the fluiddynamic mechanisms that lead to rotating stall in the Notre Dame
Stage 01 high-speed axial compressor is described. The stalling
behavior of this compressor was studied with unsteady casing
pressure measurements from a circumferentially spaced array of
sensors. In addition, over rotor casing surface streak measurements
were performed to investigate the time-averaged end-wall flow near
the rotor at operating points near stall.
Several investigative tools were applied to the analysis and
interpretation of the unsteady casing pressure data. Traditional
methods such as visual inspection, spatial Fourier decomposition,
traveling wave energy and wavelet analysis were shown to be
insufficient to characterize the pre-stall and stall inception
behavior of the compressor. A new technique based on a windowed
two-point correlation between adjacent sensors was developed and
demonstrated to provide spatial and temporal resolution of both
pre-stall and stall inception behavior.
The spatial correlation technique was then applied to the analysis
of stall inception data from experiments with asymmetric tip
clearance. The non-uniform tip clearance was produced using the
magnetic bearings which levitate the rotor shaft of the Notre Dame
Transonic Axial Compressor facility. Both steady rotor centerline
offset and rotor whirl were investigated. The results of these
experiments, along with the surface streak measurements, provide
evidence in support of recent computational observations (found in
the literature) that predict that short length scale stall inception
is related to specific features of the rotor tip clearance flow.
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