TY - GEN
T1 - Short and long length-scale disturbances leading to rotating stall in an axial compressor stage with different stator/rotor gaps
AU - Inoue, M.
AU - Kuroumaru, M.
AU - Yoshida, S.
AU - Furukawa, Masato
PY - 2001/1/1
Y1 - 2001/1/1
N2 - The transient processes of rotating stall evolution have been investigated experimentally in a low-speed axial compressor stage with three stator-rotor gaps. The pressure traces at 8 circumferential locations on the casing wall near the rotor leading edge have been analyzed by the wavelet transforms. With the appropriate mother wavelets, the evolution of short and long length-scale disturbances leading to the stall can be captured clearly. Behavior of these disturbances is different depending on the stator- rotor gap. For the large and middle gap, the stall inception is detected by a spiky short length-scale disturbance, and the number of spiky waves increases to generate the high frequency waves. They becomes the short length-scale part-span stall cells at the mild stall for the large gap, while they turn into a big stall cell with growth of a long length-scale disturbance for the middle gap. In the latter case, therefore, the stalling process was identified with 'high frequency stall inception'. For the small stator-rotor gap, the stalling process is identified with 'long wave-length stall inception', and supported the recent computational model for the short wave-length stall inception by showing that closing the rotor-stator gaps suppressed the growth of short length-scale disturbances. From the measurement of the pressure field traces on the casing wall, a hypothesis has been built up that the short length-scale disturbance should result from a separation vortex from a blade surface to reduce circulation. The processes of the stall evolution are discussed on this hypothesis.
AB - The transient processes of rotating stall evolution have been investigated experimentally in a low-speed axial compressor stage with three stator-rotor gaps. The pressure traces at 8 circumferential locations on the casing wall near the rotor leading edge have been analyzed by the wavelet transforms. With the appropriate mother wavelets, the evolution of short and long length-scale disturbances leading to the stall can be captured clearly. Behavior of these disturbances is different depending on the stator- rotor gap. For the large and middle gap, the stall inception is detected by a spiky short length-scale disturbance, and the number of spiky waves increases to generate the high frequency waves. They becomes the short length-scale part-span stall cells at the mild stall for the large gap, while they turn into a big stall cell with growth of a long length-scale disturbance for the middle gap. In the latter case, therefore, the stalling process was identified with 'high frequency stall inception'. For the small stator-rotor gap, the stalling process is identified with 'long wave-length stall inception', and supported the recent computational model for the short wave-length stall inception by showing that closing the rotor-stator gaps suppressed the growth of short length-scale disturbances. From the measurement of the pressure field traces on the casing wall, a hypothesis has been built up that the short length-scale disturbance should result from a separation vortex from a blade surface to reduce circulation. The processes of the stall evolution are discussed on this hypothesis.
UR - http://www.scopus.com/inward/record.url?scp=84905717595&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84905717595&partnerID=8YFLogxK
U2 - 10.1115/2001-GT-0341
DO - 10.1115/2001-GT-0341
M3 - Conference contribution
AN - SCOPUS:84905717595
SN - 9780791878507
T3 - Proceedings of the ASME Turbo Expo
BT - Aircraft Engine; Marine; Turbomachinery; Microturbines and Small Turbomachinery
PB - American Society of Mechanical Engineers (ASME)
T2 - ASME Turbo Expo 2001: Power for Land, Sea, and Air, GT 2001
Y2 - 4 June 2001 through 7 June 2001
ER -