Diffuser having platform vanes

Patent metadata

Field	Value
Publication number	US-10731660-B2
Application number	US-201816104671-A
Country	US
Kind code	B2
Filing date	Aug 17, 2018
Priority date	Aug 17, 2018
Publication date	Aug 4, 2020
Grant date	Aug 4, 2020

Abstract

According to some aspects of the present disclosure, a diffuser for a centrifugal compressor is provided. The diffuser may comprise an outerband casing and an innerband casing. The outerband casing may comprise an annular flowpath boundary member that has a flowpath boundary surface. The flowpath boundary member may define a plurality of vane-receiving pockets spaced about a circumference of the member. The innerband casing may comprise an annular flowpath boundary member that has a flowpath boundary surface. The flowpath boundary member may comprise a plurality of vanes spaced about a circumference of the member. Each of said plurality of vanes may comprise a vane body that extends from the flowpath boundary surface, a platform head that has a lateral dimension normal to the length of the vane body greater than the lateral dimension of the vane body, and a fillet between the platform head and the vane body. The innerband casing may be positioned so that the platform head of each of the plurality of vanes is received in a respective vane-receiving pocket defined by the flowpath boundary member of the outerband casing. When received, the fillet of each of the plurality of vanes may be adjacent the flowpath boundary surface of the flowpath boundary member of said outerband casing. The flowpath boundary surfaces of each of said casings and said vanes define a fluid flowpath in said diffuser.

First claim

What is claimed is:

1. A diffuser for a centrifugal compressor comprising:
an outerband casing comprising a first flowpath boundary member having a first flowpath boundary surface, said first flowpath boundary member defining a plurality of vane-receiving pockets spaced about a circumference of the member; and
an innerband casing comprising a second flowpath boundary member having a second flowpath boundary surface, said second flowpath boundary member comprising a plurality of vanes spaced about a circumference of the member, each of said plurality of vanes comprising a vane body extending from the second flowpath boundary surface, a platform head having a lateral dimension normal to a longitudinal length of the vane body greater than a lateral dimension of the vane body, and a fillet between the platform head and the vane body,
said innerband casing being positioned so that the platform head of each of the plurality of vanes is received in a respective vane-receiving pocket defined by the first flowpath boundary member of said outerband casing such that the fillet of each of said plurality of vanes is adjacent the first flowpath boundary surface of the first flowpath boundary member of said outerband casing,
wherein said first and second flowpath boundary surfaces of each of said casings and said vanes define a fluid flowpath in said diffuser,
wherein each of said vane-receiving pockets comprises a first pocket aperture, a second pocket aperture, and a groove positioned between the first pocket aperture and the second pocket aperture.

2. The diffuser of claim 1 , wherein the platform head comprises a first platform portion dimensioned to be positioned in the first pocket aperture, a second platform portion dimensioned to be positioned in the second pocket aperture, and a third platform portion dimensioned to interface with the groove.

3. The diffuser of claim 2 , wherein the first platform portion and the second platform portion have an axial dimension that is greater than the axial dimension of the third platform portion.

4. The diffuser of claim 1 , further comprising a fillet between the vane body and the second flowpath boundary surface of the second flowpath boundary member of said innerband casing.

5. The diffuser of claim 1 , wherein the diffuser is mounted to a static component of the compressor.

6. The diffuser of claim 1 , wherein said platform head is brazed to said first flowpath boundary member of said outerband casing.

7. The diffuser of claim 1 , wherein the platform head has a length greater than the length of the vane body.

8. The diffuser of claim 1 , wherein at least a portion of the platform head has an axial thickness greater than an axial thickness of said first flowpath boundary member of said outerband casing.

9. A diffuser for a centrifugal compressor comprising:
an outerband casing comprising a first flowpath boundary member having a first flowpath boundary surface, said first flowpath boundary member defining a plurality of vane-receiving pockets spaced about a circumference of the member; and
an innerband casing comprising a second flowpath boundary member having a second flowpath boundary surface, said second flowpath boundary member comprising a plurality of vanes spaced about a circumference of the member, each of said plurality of vanes comprising a vane body extending from the second flowpath boundary surface, and a platform head having a lateral dimension normal to a length of the vane body greater than a lateral dimension of the vane body,
said innerband casing being positioned so that the platform head of each of the plurality of vanes is received in a respective vane-receiving pocket defined by the first flowpath boundary member of said outerband casing, said innerband casing being coupled to said outerband casing by a joint between the platform head of each of the plurality of vanes and the first boundary member of said outerband casing,
wherein said first and second flowpath boundary surfaces of each of said casings and said vanes define a fluid flowpath in said diffuser,
wherein a portion of each platform head has an axial thickness less than an axial thickness of the first boundary member of said outerband casing and said portion is dimensioned to interface with a groove.

10. The diffuser of claim 9 , wherein each platform head is joined to the first boundary member of said outerband casing along the axial thickness of the first boundary member.

11. The diffuser of claim 9 , wherein each platform head is joined to the first boundary member of said outerband casing by brazing.

12. The diffuser of claim 9 , wherein each of said vane-receiving pockets comprises a first pocket aperture, a second pocket aperture, and the groove positioned between the first pocket aperture and the second pocket aperture.

13. The diffuser of claim 9 , wherein each platform head has a length greater than a length of the vane body.

14. A method of diffusing air flow comprising:
forming a fluid flowpath defined by a first annular surface, a second annular surface, and a plurality of vanes extending between the first and second annular surfaces, each of said plurality of vanes comprising a vane body extending from said first annular surface, and a platform head having a lateral dimension normal to the length of the vane body greater than the lateral dimension of the vane body, each platform head being positioned in a pocket defined by the second annular surface and joined to the second annular surface; and
supplying air flow through the fluid flowpath;
wherein each of said pockets comprises a first pocket aperture, a second pocket aperture, and a groove positioned between the first pocket aperture and the second pocket aperture.

15. The method of claim 14 , further comprising supplying the air flow from a discharge of a centrifugal compressor.

16. The method of claim 14 , wherein said platform head of each of said plurality of vanes is joined to the second annular surface by brazing.

Assignees

• Rolls Royce Corp

Inventors

• Nesteroff Michael
• Acker Jonathan
• Moncada Albert
• Templin David

Classifications

• F01D9/045 Primary

  for radial flow machines or engines · CPC title

• F05D2250/52

  Outlet · CPC title

• F04D29/444 Primary

  Bladed diffusers · CPC title

• F05D2260/941

  particularly aimed at mechanical or thermal stress reduction · CPC title

• F05D2230/237

  Brazing · CPC title