Airfoil with hybrid drilled and cutback trailing edge

Patent metadata

Field	Value
Publication number	US-9422816-B2
Application number	US-49266309-A
Country	US
Kind code	B2
Filing date	Jun 26, 2009
Priority date	Jun 26, 2009
Publication date	Aug 23, 2016
Grant date	Aug 23, 2016

Abstract

An apparatus for a gas turbine engine includes an airfoil, a metering opening for metering a cooling fluid, a cutback slot configured to deliver the cooling fluid from the metering opening, and a cooling hole. The airfoil defines a trailing edge, opposite first and second faces, and a mean camber line. The cutback slot is defined along the first face of the airfoil adjacent to the trailing edge and offset from the mean camber line of the airfoil. The cooling hole has an outlet that is located at the trailing edge and substantially aligned with the mean camber line of the airfoil. The cooling hole delivers a portion of the cooling fluid from the metering opening.

First claim

The invention claimed is:

1. An apparatus for a gas turbine engine, the apparatus comprising:
an airfoil defining a trailing edge, opposite first and second faces, and a mean camber line;
a metering opening for metering a cooling fluid;
a cutback slot configured to deliver the cooling fluid from the metering opening, the cutback slot defined along the first face of the airfoil adjacent to the trailing edge and offset from the mean camber line of the airfoil; and
a cooling hole having an outlet that is located at the trailing edge and substantially aligned with the mean camber line of the airfoil, wherein the cooling hole delivers a portion of the cooling fluid from the metering opening, wherein the cutback slot defines an upstream boundary at the first face of the airfoil, and wherein the cooling hole defines an inlet located at or downstream from the upstream boundary of the cutback slot.

2. The apparatus of claim 1 , and further comprising:
a cooling fluid supply plenum extending at least partially in a spanwise direction through an interior portion of the airfoil, the cooling fluid supply plenum configured to supply the cooling fluid to the metering opening for both the cutback slot and the cooling hole.

3. The apparatus of claim 1 , wherein the cutback slot has a diverging shape.

4. The apparatus of claim 1 , wherein the cooling hole extends in a chordwise direction.

5. The apparatus of claim 1 , wherein the trailing edge is radiused.

6. The apparatus of claim 5 , wherein the trailing edge defines a first diameter and the cooling hole defines a second diameter, and wherein the first diameter is at least three times greater than the second diameter.

7. The apparatus of claim 1 , wherein the cooling hole and the cutback slot are substantially aligned in a spanwise direction along the airfoil.

8. The apparatus of claim 1 , wherein an outlet area of the cutback slot is larger than an area of the outlet of the cooling hole.

9. The apparatus of claim 1 , wherein the first face is a pressure face and the second face is a suction face.

10. A method comprising:
casting an airfoil, wherein casting defines a cutback slot at a pressure side of the airfoil adjacent to a trailing edge of the airfoil; and
removing material of the airfoil subsequent to casting to define a cooling hole from the cutback slot to the trailing edge of the airfoil.

11. The method of claim 10 , wherein removing material of the airfoil to define the cooling hole comprises drilling.

12. The method of claim 10 , wherein a plurality of spaced apart cutback slots are defined during the casting step.

13. The method of claim 12 , wherein a plurality of cooling holes are defined during the step of removing material of the airfoil, each of the plurality of cooling holes defined relative to one of the plurality of spaced apart cutback slots.

14. The method of claim 10 and further comprising:
providing a cooling fluid;
delivering at least a portion of the cooling fluid through the cutback slot; and
delivering at least some of the cooling fluid from the cutback slot through the cooling hole.

15. An airfoil comprising:
a pressure face;
a suction face located opposite the pressure face;
a mean camber line defined midway between the pressure and suction faces;
a trailing edge substantially aligned with the mean camber line;
a plurality of trailing edge cooling passages spaced from one another in a spanwise direction, wherein each of the trailing edge cooling passages comprises:
a first portion that defines an outlet arranged along the pressure face of the airfoil, wherein the outlet of the first portion is configured as a cutback slot to provide film cooling; and
a second portion that defines an outlet at the trailing edge, the outlet of the second portion substantially aligned with the mean camber line to provide convective cooling,
wherein the outlet of the first portion is larger than the outlet of the second portion.

16. The airfoil of claim 15 , wherein the plurality of trailing edge cooling passages having the second portion are located exclusively in a region between 30% to 80% of a span of the airfoil.

17. The apparatus of claim 15 , wherein the outlet of the cutback slot defines an upstream boundary at the pressure face of the airfoil, and wherein the inlet of the second portion is located at or downstream from the upstream boundary of the outlet of the cutback slot.

18. The airfoil of claim 15 , wherein the trailing edge is radiused and defines a first diameter, wherein the outlet of the second portion defines a second diameter, and wherein the first diameter is at least three times greater than the second diameter.

19. A method comprising:
delivering a cooling fluid to a cutback slot at a pressure face of an airfoil adjacent to a trailing edge of the airfoil to provide film cooling; and
delivering a portion of the cooling fluid from the cutback slot where film cooling is provided through the trailing edge of the airfoil to provide convective cooling.

Assignees

• Spangler Brandon W
• Draper Sam
• United Technologies Corp

Inventors

• Spangler Brandon W
• Draper Sam

Classifications

• F05D2240/122

  related to the trailing edge of a stator vane · CPC title

• F05D2240/304

  related to the trailing edge of a rotor blade · CPC title

• F01D5/186

  Film cooling (F01D5/187 takes precedence) · CPC title

• F05D2230/10

  by removing material · CPC title

• F05D2260/202

  by film cooling · CPC title