Compressor bleed self-recirculating system

摘要

A compressor (20) for a gas turbine engine having a bleed air recirculation system includes a plurality of bleed holes (36) extending through a shroud (32) at a first axial location thereon substantially adjacent the rotor blade tips (28). The bleed holes (36) have a closed outer perimeter along their complete length. An annular bleed cavity (38) surrounds the shroud (32) and is in communication with outlet openings (35) of the bleed holes (36). The bleed holes provide communication between said main gas flow passage and the bleed cavity (38). The bleed cavity (38) includes exit passages having outlets (39) disposed in said shroud (32) at a second axial location which is upstream of both the first axial location and the leading edge (46) of the blades (28) of the rotor (24). Bleed air is passively bled from the main gas flow passage via the bleed holes (36), recirculated through the bleed cavity (38) and re-injected back into the main gas flow passage at the second axial location.