SYSTEM AND METHOD FOR COOLING TURBINE BLADES

• US 20130177446A1
• Filed: 01/05/2012
• Published: 07/11/2013
• Est. Priority Date: 01/05/2012
• Status: Active Grant

• Current Assignee: GE Infrastructure Technology, LLC (GE Vernova, Inc.)
• Original Assignee: General Electric Company
• Inventors: Smith, Aaron Ezekiel, Penny, Christopher Michael
• Granted Patent: US 9,051,842 B2
• Time in Patent Office: Days
• US Class Current: 416/97.R
• CPC Class Codes: F01D 25/12 Cooling
• CPC Class Codes: F01D 5/186 Film cooling F01D5/187 takes precedence
• CPC Class Codes: F01D 5/187 Convection cooling
• CPC Class Codes: F05D 2230/21 by casting
• CPC Class Codes: F05D 2240/304 related to the trailing edge of a rotor blade
• CPC Class Codes: F05D 2250/131 polygonal
• CPC Class Codes: F05D 2250/323 convergent
• CPC Class Codes: F05D 2260/202 by film cooling
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

A system includes a turbine blade, which includes at least one cooling slot configured to convey a coolant in a flow direction from an interior to an exterior of the turbine blade. The cooling slot includes an entrance coupled to the interior and a converging section downstream from the entrance. The converging section includes a first cross-sectional area that decreases in the flow direction. The cooling slot also includes an exit disposed along a trailing edge of the turbine blade.

Claims

1. A system, comprising:

a turbine blade comprising at least one cooling slot configured to convey a coolant in a flow direction from an interior to an exterior of the turbine blade, wherein the cooling slot comprises;

an entrance coupled to the interior;

a converging section downstream from the entrance, wherein the converging section comprises a first cross-sectional area that decreases in the flow direction; and

an exit disposed along a trailing edge of the turbine blade.

2. The system of claim 1, comprising a metering section downstream from the converging section, wherein the metering section comprises a second cross-sectional area that is substantially constant in the flow direction.

3. The system of claim 2, wherein the converging section comprises a first length in the flow direction, the metering section comprises a second length in the flow direction, and the first length is greater than the second length.

4. The system of claim 1, wherein the exit is not disposed on a pressure side or a suction side of the turbine blade.

5. The system of claim 1, wherein the exit is disposed along a midline of the trailing edge.

6. The system of claim 1, wherein the converging section comprises a height and a width, wherein both the height and the width decrease in the flow direction.

7. The system of claim 6, wherein the height and the width are different from one another.

8. The system of claim 1, comprising an expanding section downstream from the converging section, wherein the expanding section comprises a third cross-sectional area that increases in the flow direction.

9. The system of claim 1, wherein a cross-sectional shape of the converging section comprises at least one of a circle, an oval, a square, a rectangle, or a polygon, or a combination thereof.

10. The system of claim 1, comprising a turbine having the turbine blade.

11. A system, comprising:

a rotary blade, comprising;

a leading edge;

a trailing edge;

a pressure sidewall;

a suction sidewall;

a cooling cavity disposed between the pressure sidewall and the suction sidewall; and

a plurality of cooling slots coupled to cooling cavity, wherein the plurality of cooling slots is configured to pass a coolant in a flow direction through the trailing edge and each of the plurality of cooling slots comprises;

a converging section comprising a first cross-sectional area that decreases in the flow direction;

a metering section coupled to the converging section, wherein the metering section comprises a second cross-sectional area that is substantially constant in the flow direction; and

an exit disposed along the trailing edge.

12. The system of claim 11, wherein the exit is not disposed on the pressure sidewall or the suction sidewall.

13. The system of claim 11, wherein each converging section comprises a height and a width, wherein both the height and the width decrease in the flow direction.

14. The system of claim 11, wherein each converging section comprises a first length in the flow direction, each metering section comprises a second length in the flow direction, and a ratio of the first length to the second length is greater than approximately 5:

1.

15. The system of claim 11, comprising an expanding section downstream from the converging section, wherein the expanding section comprises a third cross-sectional area that increases in the flow direction.

16. The system of claim 11, comprising a turbomachine having the rotary blade, wherein the rotary blade is disposed on a rotor, a stator, or both the rotor and stator.

17. A method, comprising:

forming a ceramic turbine blade core;

inserting the core into a die; and

casting a turbine blade between the core and the die with a pressure sidewall and a suction sidewall coupled together at a leading edge and a trailing edge, wherein the turbine blade comprises a plurality of cooling slots configured to pass a coolant in a flow direction through the trailing edge, and each of the plurality of cooling slots comprises;

a converging section comprising a first cross-sectional area that decreases in the flow direction;

a metering section coupled to the converging section, wherein the metering section comprises a second cross-sectional area that is substantially constant in the flow direction; and

an exit disposed along the trailing edge.

18. The method of claim 17, wherein the exit is disposed along a midline of the trailing edge.

19. The method of claim 17, wherein the first cross-sectional area of the converging section decreases in at least two dimensions.

20. The method of claim 17, wherein the converging section comprises a first length in the flow direction, the metering section comprises a second length in the flow direction, and the first length is greater than the second length.