Single slot impeller bleed

A compressor for a gas turbine engine which includes a stationary annular shroud having an inlet end and an outlet end and an inner surface;

• a rotor located within the shroud including a plurality of blades directed radially and outwardly from the rotor, each blade having an outer tip that is of similar contour to and located in a close spaced relationship to the inner surface of the shroud;
• the annular shroud comprising:
• a upstream annular segment and a downstream annular segment axially spaced apart at a fixed distance to form a circumferentially continuous annular slot therebetween, the annular slot extending through the shroud, the upstream annular segment being supported by a first structure and the downstream annular segment being supported by a second structure, each of the upstream and downstream annular segments being independent and self-supporting at a peripheral edge adjacent the slot so that when the compressor is in operation, air passes through the continuous annular slot without causing a dynamic component which affects the blades.

A method for providing an air bleed passage in association with a compressor for use in gas turbine engines, the compressor having an impeller assembly which includes an impeller rotor rotatably supported within an annular shroud having an inlet and an outlet, comprising:

• producing the impeller shroud in two separate annular segments having an upstream annular segment and downstream annular segment;
• supporting the upstream and downstream annular segments separately and independently in an axially fixed separated relationship to form a circumferentially continuous, uninterrupted annular slot therebetween, such that the annular slot extends through the shroud.