Patent ID: 6589015
Filing Date: 2003-07-08
Classification: F01D,F04D,F05D

Abstract:
A centrifugal compressor including an impeller and a diffuser, the impeller having an inner integral hub with vanes thereon, being adapted to rotate within an outer shroud about a central longitudinal axis, and having a defined hub-to-shroud distribution of fluid exit angles, the diffuser, being downstream from the impeller, comprising:a plurality of circumferentially spaced discrete passages at least partially defining fluid paths through the diffuser, and being angled such that adjacent discrete passages intersect each other to form an annular semi-vaneless diffuser inlet space; the discrete passages downstream of the semi-vaneless space each having an inlet therefrom and an outlet with a greater cross-sectional area than the inlet; the intersection of the annular semi-vaneless space and each discrete passage defining a leading edge thereof; each discrete passage being defined by a wall bounding a cross-sectional area, the wall comprising at least a first substantially rectilinear portion and a second opposed convexly curved portion; the first substantially rectilinear portion being adjacent the hub of the impeller and the second opposed convexly curved portion being adjacent the outer shroud; and the leading edge of each discrete diffuser passage providing a close incidence angle match with the fluid exit angles of the impeller.