Airfoil with improved internal cooling channel pedestals

• US 9,297,261 B2
• Filed: 03/07/2012
• Issued: 03/29/2016
• Est. Priority Date: 03/07/2012
• Status: Active Grant

• Current Assignee: Rtx Corporation
• Original Assignee: United Technologies Corporation (Rtx Corporation)
• Inventors: Otero, Edwin
• Primary Examiner(s): EDGAR, RICHARD A
• Application Number:
  US13/413,969
• Publication Number:
  US 20130232991A1
• Time in Patent Office: 1,483 Days
• US Class Current: 1/1
• CPC Class Codes: F01D 5/187 Convection cooling
• CPC Class Codes: F01D 5/188 with an insert in the blade cavity to guide the cooling fluid, e.g. forming a separation wall
• CPC Class Codes: F05D 2240/304 related to the trailing edge of a rotor blade
• CPC Class Codes: F05D 2250/14 elliptical
• CPC Class Codes: F05D 2250/231 cylindrical
• CPC Class Codes: F05D 2260/202 by film cooling
• CPC Class Codes: F05D 2260/2214 by increasing the heat transfer surface

Abstract

An airfoil for a turbine engine, the airfoil including a first side wall, a second side wall spaced apart from the first side wall, and an internal cooling channel formed between the first side wall and the second side wall. The internal cooling channel includes at least one pedestal having a first pedestal end connected to the first side wall and a second pedestal end connected to the second side wall. The internal cooling channel also includes a first fillet disposed around the periphery of the first pedestal end between the first side wall and the first pedestal end; and a second fillet disposed around the periphery of the second pedestal end between the second side wall and the second pedestal end. At least one of the first fillet and the second fillet includes a profile that is non-uniform around the periphery of the corresponding pedestal end.

Claims

1. An airfoil for a turbine engine, the airfoil comprising:

a first side wall;

a second side wall spaced apart from the first side wall;

an internal cooling channel formed between the first side wall and the second side wall, the internal cooling channel comprising;

at least one pedestal having a first pedestal end connected to the first side wall and a second pedestal end connected to the second side wall;

a first fillet disposed around the periphery of the first pedestal end between the first side wall and the first pedestal end; and

a second fillet disposed around the periphery of the second pedestal end between the second side wall and the second pedestal end;

wherein at least one of the first fillet and the second fillet includes a profile that is non-uniform around the periphery of the corresponding pedestal end, further wherein the profile is a simple curve described at any point around the periphery of the corresponding pedestal end by a radius of curvature at a point;

the profile at a first point includes a first local maximum value of the radius of curvature;

the first point being a point around the periphery nearest a leading edge of the airfoil;

a trailing edge;

a pressure side wall connecting the leading edge and the trailing edge; and

a suction side wall spaced apart from the pressure side wall, the suction side wall connecting the leading edge and the trailing edge;

wherein the pressure side wall is the first side wall and the suction side wall is the second side wall.

2. The airfoil of claim 1, wherein the airfoil is one of a turbine rotor blade and a turbine stator vane.

3. The airfoil of claim 1, wherein the pedestal is one of a cylinder and an elliptic cylinder.

4. The airfoil of claim 1, wherein the profile at a second point includes a second local maximum value of the radius of curvature, the second point being a point around the periphery nearest the trailing edge.

5. The airfoil of claim 1, wherein the profile is a compound curve described at any point by a first radius of curvature describing a first portion of the profile at that point and a second radius of curvature describing a second portion of the profile at that point, each radius having a different center point;

the first portion being closer to the corresponding one of the pressure side wall and the suction side wall than the second portion;

the profile at a first point includes a first local maximum value of the first radius of curvature;

the first point being a point around the periphery nearest the leading edge.

6. The airfoil of claim 1, wherein the profile is a simple curve described at any point by a radius of curvature at that point;

the profile at a first point includes a first local maximum value of the radius of curvature;

the first point between a second point around the periphery nearest the leading edge, and a third point around the periphery nearest the trailing edge.

7. The airfoil of claim 6, wherein the first point is closer to the second point than to the third point.

8. The airfoil of claim 7, further comprising:

a platform from which the leading edge, trailing edge, pressure side wall, and suction side wall extend;

wherein the first point is closer to the platform than either of the second point or the third point.

9. The airfoil of claim 7, further comprising:

a platform from which the leading edge, trailing edge, pressure side wall, and suction side wall extend;

wherein the first point is farther from the platform than either of the second point or the third point.

10. A gas turbine engine comprising:

a compressor section;

a combustor section; and

a turbine including;

a plurality of airfoils, at least one of the plurality of airfoils including;

a first side wall;

a second side wall spaced apart from the first side wall;

an internal cooling channel formed between the first side wall and the second side wall, the internal cooling channel comprising;

at least one pedestal having a first pedestal end connected to the first side wall and a second pedestal end connected to the second side wall;

a first fillet disposed around the periphery of the first pedestal end between the first side wall and the first pedestal end; and

a second fillet disposed around the periphery of the second pedestal end between the second side wall and the second pedestal end;

wherein at least one of the first fillet and the second fillet includes a profile that is non-uniform around the periphery of the corresponding pedestal end, further wherein the profile is a simple curve described at any point around the periphery of the corresponding pedestal end by a radius of curvature at a point;

the profile at a first point includes a first local maximum value of the radius of curvature;

the first point being a point around the periphery nearest a leading edge of the airfoil;

a trailing edge;

a pressure side wall connecting the leading edge and the trailing edge; and

a suction side wall spaced apart from the pressure side wall, the suction side wall connecting the leading edge and the trailing edge;

wherein the pressure side wall is the first side wall and the suction side wall is the second side wall.

11. The engine of claim 10, wherein the at least one of the plurality of airfoils is one of a rotor blade and a stator vane.

12. The engine of claim 10, wherein the pedestal is one of a cylinder and an elliptic cylinder.

13. The engine of claim 10, wherein the profile at a second point includes a second local maximum value of the radius of curvature, the second point being a point around the periphery nearest the trailing edge.

14. The engine of claim 10, wherein the profile is a compound curve described at any point by a first radius of curvature describing a first portion of the profile at that point and a second radius of curvature describing a second portion of the profile at that point, each radius having a different center point;

the first portion being closer to the corresponding one of the pressure side wall and the suction side wall than the second portion;

the profile at a first point includes a first local maximum value of the first radius of curvature;

the first point being a point around the periphery nearest the leading edge.

15. The engine of claim 10, wherein the profile is a simple curve described at any point by a radius of curvature at that point;

the profile at a first point includes a first local maximum value of the radius of curvature;

the first point between a second point around the periphery nearest the leading edge, and a third point around the periphery nearest the trailing edge.

16. The engine of claim 15, wherein the first point is closer to the second point than to the third point.

17. The engine of claim 16, further comprising:

a platform from which the leading edge, trailing edge, pressure side wall, and suction side wall extend;

wherein the first point is closer to the platform than either of the second point or the third point.

18. The engine of claim 16, further comprising:

a platform from which the leading edge, trailing edge, pressure side wall, and suction side wall extend;

wherein the first point is farther from the platform than either of the second point or the third point.

19. A method for providing enhanced gas turbine engine airfoil durability, the method comprising:

introducing cooling air into an internal cooling channel within the airfoil;

flowing the cooling air through the internal cooling channel past pedestals connected to walls of the airfoil;

the internal cooling channel including fillets at pedestal ends, at least some of the fillets including a profile that is non-uniform around the periphery of the corresponding pedestal end, wherein the profile is a simple curve described at any point around the periphery of the corresponding pedestal end by a radius of curvature at a point;

the profile at a first point includes a first local maximum value of the radius of curvature;

the first point being a point around the periphery nearest a leading edge of the airfoil; and

exhausting cooling air through trailing edge cooling slots.