US 9,810,157 B2
Compressor shroud reverse bleed holes
Jason Nichols, Mississauga (CA); Peter Townsend, Mississauga (CA); Hien Duong, Mississauga (CA); and Vijay Kandasamy, Tamil Nadu (IN)
Assigned to PRATT & WHITNEY CANADA CORP., Longueuil (CA)
Filed by Pratt & Whitney Canada Corp., Longueuil (CA)
Filed on Mar. 4, 2013, as Appl. No. 13/783,773.
Prior Publication US 2014/0286746 A1, Sep. 25, 2014
Int. Cl. F02C 9/18 (2006.01); F01D 5/14 (2006.01); F04D 29/68 (2006.01); F02C 3/04 (2006.01); F04D 27/02 (2006.01); F04D 29/52 (2006.01)
CPC F02C 9/18 (2013.01) [F01D 5/145 (2013.01); F02C 3/04 (2013.01); F04D 27/023 (2013.01); F04D 29/526 (2013.01); F04D 29/682 (2013.01); Y02T 50/671 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A compressor for a gas turbine engine comprising:
a rotor having a hub defining a central axis of rotation and a plurality of blades radially extending from the hub to project into an annular gas flow passage of said compressor, each of said blades having a remote blade tip and a leading edge defined between opposed pressure and suction surfaces, said rotor being rotatable about said axis of rotation in a direction of rotation;
an annular shroud circumferentially surrounding the rotor and having a radially inner surface adjacent to the blade tips, the inner surface of the shroud facing said annular gas flow passage; and
a plurality of bleed holes extending through said shroud adjacent said blade tips, the bleed holes providing gas flow communication between said annular gas flow passage and a region outside the shroud, each of said bleed holes having an inlet end disposed in the radially inner surface of the shroud adjacent the blade tips to communicate with the annular gas flow passage, each of said bleed holes having an outlet end disposed in a radially outer surface of the shroud, bleed air removed from the annular gas flow passage by the bleed holes flowing in a bleed flow direction from the inlet end to the outlet end of the bleed holes, the outlet end of each of said bleed holes being located circumferentially upstream of the inlet end thereof, and the bleed flow direction at the radially inner surface of the shroud has a circumferential component that is opposite to the direction of rotation of the rotor.