Experimental investigation on stall characteristics on rotor tip end-wall

In order to study the stall characteristics on rotor tip end-wall, the throttling characteristics of a single-stage low-speed axial compressor was experimentally investigated. Dynamic pressure signals were collected during the throttling process by high-response transducers on casing wall at rotor tip chord-wise location. Casing pressure contour and casing pressure RMS contour were conducted to analyze dynamic pressure signals. The results indicate that tip leakage vortex trajectory and starting position move to rotor leading-edge as the compressor runs toward stall, and tip leakage vortex trajectory spillages to leading-edge of the rotor in adjacent blade passage at stall. Stall cell scale in circumference extends as the compressor runs toward deep stall. Two stall cells rotate in circumference as the compressor exits from the stall and their circumferential scale reduces, however, their rotating frequency is about 30 Hz and remains almost unchanged. Finally two stall cells merged into one 3 rotor revolutions before exiting stall.