Diffuser for centrifugal compressor

• US 20050111974A1
• Filed: 07/09/2004
• Published: 05/26/2005
• Est. Priority Date: 09/24/2003
• Status: Active Grant

• Current Assignee: GE Global Sourcing LLC (Westinghouse Air Brake Technologies Corporation)
• Original Assignee: General Electric Company
• Inventors: Furman, Anthony Holmes, Swenson, Kendall Roger, Loringer, Daniel Edward, Dillen, Eric Richard
• Granted Patent: US 7,101,151 B2
• Time in Patent Office: Days
• US Class Current: 415/211.200
• CPC Class Codes: F04D 29/444 Bladed diffusers
• CPC Class Codes: F04D 29/681 especially adapted for elastic fluid pumps
• CPC Class Codes: F04D 29/682 by fluid extraction
• CPC Class Codes: F04D 29/684 by fluid injection
• CPC Class Codes: F05D 2240/121 related to the leading edge of a stator vane
• CPC Class Codes: F05D 2250/52 Outlet

Abstract

A diffuser (30) for a centrifugal compressor (60) having a flow slot (34) formed between the leading edge portion (36) of a diffuser vane (32) and an adjoining diffuser wall (70) for the passage of working fluid (67) over the vane from the pressure side ((40) to the suction side (42) of the vane. The portion (38) of the working fluid passing over the vane is injected into the flow boundary region (43), thereby minimizing the growth of a flow separation zone (58) along the suction side.

Claims

1. A diffuser for a compressor, the diffuser comprising:

opposed walls defining a space disposed downstream of a compressor impeller for receiving a flow of a working fluid from the impeller;

a vane comprising a pressure side and a suction side connected between the opposed walls for directing the working fluid through the space; and

a flow slot formed between the vane and one of the walls, the flow slot extending along a portion of the vane upstream from a throat of the vane for allowing a portion of the flow of working fluid to pass from the pressure side to the suction side of the vane to suppress expansion of a flow separation zone on the suction side of the vane.

2. The diffuser of claim 1, wherein the flow slot comprises a groove formed into a surface of the vane prior to that surface being connected to a respective adjacent one of the walls.

3. The diffuser of claim 1, wherein the flow slot extends to a leading edge of the vane.

4. The diffuser of claim 1, wherein the slot is formed to extend downstream from a point downstream of a leading edge of the vane to define a support connection between the vane and the one of the walls at the leading edge.

5. The diffuser of claim 1, wherein the flow slot comprises a height perpendicular to a chord of the vane of no more than 5% of a total height of the vane perpendicular to the chord of the vane.

6. The diffuser of claim 1, wherein the flow slot comprises a height perpendicular to a chord of the vane of no more than 10% of a total height of the vane perpendicular to the chord of the vane.

7. The diffuser of claim 1, wherein the flow slot extends along no more than 25% of a chord length of the vane.

8. The diffuser of claim 1, wherein the flow slot extends along no more than 38% of a chord length of the vane.

9. The diffuser of claim 1, wherein the flow slot extends along at least 5% of a chord length of the vane.

10. A compressor comprising the diffuser of claim 1.

11. A diffuser for a compressor, the diffuser comprising:

opposed walls defining a space disposed downstream of a compressor impeller for receiving a flow of a working fluid from the impeller;

a vane comprising a pressure side and a suction side connected between the opposed walls for directing the working fluid through the space; and

a flow opening having an inlet on the pressure side of the vane and an outlet on the suction side of the vane upstream from a throat location on the vane for allowing a portion of the flow of working fluid to pass from the pressure side to the suction side of the vane.

12. The diffuser of claim 11, wherein the flow opening comprises a first flow opening formed proximate a first of the opposed walls allowing a first portion of the flow of working fluid to pass from the pressure side to the suction side of the vane, and further comprising a second flow opening formed proximate a second of the opposed walls allowing a second portion of the flow of working fluid to pass from the pressure side to the suction side of the vane.

13. The diffuser of claim 11, wherein the flow opening comprises a hole drilled between the pressure side and the suction side of the vane.

14. The diffuser of claim 11, wherein the flow opening is formed in one of the opposed walls.

15. The diffuser of claim 11, wherein a height of the flow opening perpendicular to a chord of the vane is no more than 5% of a total height of the vane.

16. The diffuser of claim 11, wherein a height of the flow opening perpendicular to a chord of the vane is no more than 10% of a total height of the vane.

17. The diffuser of claim 11, wherein the flow opening is formed proximate an intersection of the vane and one of the opposed walls.

18. The diffuser of claim 11, wherein the flow opening comprises a flow slot formed between the vane and one of the opposed walls.

19. The diffuser of claim 11, wherein the flow opening extends downstream from a point downstream of a leading edge of the vane to define a support connection between the vane and the opposed walls at the leading edge.

20. A compressor comprising the diffuser of claim 11.