Turbine blade with tip sealing and cooling

• US 8,182,221 B1
• Filed: 07/29/2009
• Issued: 05/22/2012
• Est. Priority Date: 07/29/2009
• Status: Expired due to Fees

• Current Assignee: Florida Turbine Technologies, Inc. (Kratos Defense & Security Solutions Incorporated)
• Original Assignee: Florida Turbine Technologies, Inc. (Kratos Defense & Security Solutions Incorporated)
• Inventors: Liang, George
• Primary Examiner(s): Kershteyn, Igor
• Application Number:
  US12/511,205
• Time in Patent Office: 1,028 Days
• Field of Search: 415/1, 415/115, 415/173.5, 415/174.4, 416/1, 416/90.R, 416/92, 416/96.R, 416/97.R
• US Class Current: 416/1
• CPC Class Codes: F01D 11/20 Actively adjusting tip-clearance
• CPC Class Codes: F01D 5/087 in the radial passages of the rotor disc
• CPC Class Codes: F01D 5/145 Means for influencing boundary layers or secondary circulations for compressors F04D29/68
• CPC Class Codes: F01D 5/186 Film cooling F01D5/187 takes precedence
• CPC Class Codes: F01D 5/187 Convection cooling
• CPC Class Codes: F01D 5/20 Specially-shaped blade tips to seal space between tips and stator F01D5/225 takes precedence
• CPC Class Codes: F05D 2260/202 by film cooling

Abstract

A turbine rotor blade with a tip region cooling and sealing circuit that includes a squealer tip with a continuous tip rail, the pressure side tip rail being offset from the pressure side wall, the pressure ad suction side tip rails both include concave shaped deflector surfaces on the forward side walls and a row of air jet passages opening onto a top surface of the tip rails, and with radial near wall cooling channels formed within the pressure side and suction side walls to provide near wall cooling, and where the pressure side radial cooling channels supplies the cooling air to the tip rail deflectors to form a vortex flow on the forward side wall of the tip rails, and the suction side radial cooling channels supplies cooling air to the tip rail air jet passages to discharge cooling air to block the on-coming leakage flow across the blade tip. Tip floor cooling passages connect the pressure side radial cooling channels to the suction side deflector surface that alternate with tip floor cooling passages that connect the suction side radial cooling channels to the pressure side tip rail air jet passages.

Claims

1. A turbine rotor blade comprising:

an airfoil section having a pressure side wall and a suction side wall;

a cooling air cavity formed between the pressure side wall and the suction side wall;

a pressure side tip rail and a suction side tip rail forming a squealer pocket on a tip floor;

the pressure side tip rail being offset from the pressure side wall of the airfoil;

the suction side tip rail includes an aft side wall that is both flush with the suction side airfoil wall and slanted in a direction towards the pressure side wall; and

,

both the pressure side tip rail and the suction side tip rail includes a flat top surface;

the forward side walls of the pressure side tip rail and the suction side tip rail both include concave shaped deflector surfaces; and

,

radial cooling channels formed within the pressure side wall of the airfoil and connected to the pressure side and suction side tip rail deflectors to discharge cooling air into the deflectors.

3. The turbine rotor blade of claim 1, and further comprising:

the pressure side wall radial cooling channels are connected to the suction side tip rail deflector through tip floor cooling passages.

5. The turbine rotor blade of claim 3, and further comprising:

the pressure side tip rail and the suction side tip rail both include a row of air jet passages opening onto the flat top surfaces of the tip rails and connected to radial cooling channels formed within the suction side wall of the airfoil;

the suction side wall radial cooling channels are connected to the pressure side tip rail air jets passages through tip floor cooling passages; and

,

the tip floor channels that connect the pressure side wall radial channels to the deflectors alternate along the tip floor with the tip floor channels that connect the suction side wall radial channels to the tip rail air jet passages.

2. A turbine rotor blade comprising:

an airfoil section having a pressure side wall and a suction side wall;

a cooling air cavity formed between the pressure side wall and the suction side wall;

a pressure side tip rail and a suction side tip rail forming a squealer pocket on a tip floor;

the pressure side tip rail being offset from the pressure side wall of the airfoil;

the suction side tip rail includes an aft side wall that is both flush with the suction side airfoil wall and slanted in a direction towards the pressure side wall; and

,

both the pressure side tip rail and the suction side tip rail includes a flat top surface; and

,

the pressure side tip rail and the suction side tip rail both include a row of air jet passages opening onto the flat top surfaces of the tip rails and connected to radial cooling channels formed within the suction side wall of the airfoil.

4. The turbine rotor blade of claim 2, and further comprising:

the suction side wall radial cooling channels are connected to the pressure side tip rail air jets passages through tip floor cooling passages.

6. A turbine rotor blade comprising:

an airfoil section having a pressure side wall and a suction side wall;

a cooling air cavity formed between the pressure side wall and the suction side wall;

a pressure side tip rail and a suction side tip rail forming a squealer pocket on a tip floor;

the pressure side tip rail being offset from the pressure side wall of the airfoil;

the suction side tip rail includes an aft side wall that is both flush with the suction side airfoil wall and slanted in a direction towards the pressure side wall; and

,

both the pressure side tip rail and the suction side tip rail includes a flat top surface;

a cooling air supply cavity formed between the pressure side wall and the suction side wall of the airfoil;

a metering hole to connect a cooling air inlet cavity formed within a root section of the blade to the cooling air supply cavity; and

,

the cooling air supply cavity is not fluidly connected to radial cooling channels or tip floor cooling channels.

7. The turbine rotor blade of claim 6, and further comprising:

the cooling air supply cavity is located in a leading edge region of the airfoil; and

,

a showerhead arrangement of film cooling holes is connected to the leading edge cooling air supply cavity.

8. The turbine rotor blade of claim 6, and further comprising:

the cooling air supply cavity is located in a trailing edge region of the airfoil; and

,

a row of exit cooling holes located in the trailing edge region of the airfoil is connected to the trailing edge cooling air supply cavity.

9. A turbine rotor blade comprising:

an airfoil section having a pressure side wall and a suction side wall;

a cooling air cavity formed between the pressure side wall and the suction side wall;

a pressure side tip rail and a suction side tip rail forming a squealer pocket on a tip floor;

the pressure side tip rail and the suction side tip rail both include a concave shaped deflector on a forward side wall of the tip rail;

the pressure side tip rail and the suction side tip rail both include a row of air jet passages opening onto a top surface of the tip rail; and

,

the deflectors and the air jet passages being connected to a cooling air passage within the airfoil such that cooling air is discharged into the deflectors and out from the air jet passages.

10. The turbine rotor blade of claim 9, and further comprising:

the tip rail deflectors are connected to a plurality of pressure side wall radial cooling channels; and

,

the tip rail air jet passages are connected to a plurality of suction side radial wall cooling channels.

11. The turbine rotor blade of claim 9, and further comprising:

the tip rail is a continuous tip rail around the leading edge;

the pressure side tip rail is offset from the pressure side wall of the airfoil; and

,

the pressure side tip rail and the suction side tip rail both have aft side walls that slant toward the pressure side wall.

12. The turbine rotor blade of claim 9, and further comprising:

the air jet passages in both tip rails are slanted toward the pressure side wall.

13. The turbine rotor blade of claim 10, and further comprising:

the suction side tip rail deflector is connected to the plurality of pressure side wall radial cooling channels through a plurality of tip floor cooling channels; and

,

the pressure side tip rail air jet passages are connected to the plurality of suction side wall radial cooling channels through a plurality of tip floor cooling channels.

14. A turbine rotor blade comprising:

an airfoil section with a pressure side wall and a suction side wall;

a cooling air cavity formed between the two side walls;

a plurality of pressure side radial near wall cooling passages formed within the pressure side wall of the airfoil;

a plurality of suction side radial near wall cooling passages formed within the suction side wall of the airfoil;

a tip floor having a plurality of tip floor cooling channels connected to the pressure side radial cooling channels;

the tip floor having a plurality of tip floor cooling channels connected to the suction side radial cooling channels; and

,

the pressure side tip floor cooling channels and the suction side tip floor cooling channels alternating along the tip floor.

15. The turbine rotor blade of claim 14, and further comprising:

a pressure side tip rail offset from a pressure side wall of the airfoil;

a suction side tip rail; and

,

an aft side wall of both tip rails being slanted toward the pressure side wall.

16. The turbine rotor blade of claim 14, and further comprising:

a pressure side tip rail offset from a pressure side wall of the airfoil;

a suction side tip rail; and

,

the pressure side tip rail and the suction side tip rail both include a concave shaped deflector on a forward side wall of the tip rail.

17. The turbine rotor blade of claim 14, and further comprising:

a pressure side tip rail offset from a pressure side wall of the airfoil;

a suction side tip rail; and

,

the pressure side tip rail and the suction side tip rail both include a row of air jet passages opening onto a top surface of the tip rail.

18. A process for cooling and sealing a tip region of a turbine rotor blade, the turbine rotor blade includes an airfoil section with a pressure side wall and a suction side wall with a cooling air cavity formed between the two side walls, the turbine rotor blade also includes a continuous tip rail with a pressure side tip rail offset from the pressure side wall and a suction side tip rail flush with the suction side wall, the process comprising the steps of:

passing cooling air through the pressure side wall to produce near wall cooling of the pressure side wall;

passing cooling air through the suction side wall to produce near wall cooling of the suction side wall;

discharging the cooling air from the pressure side wall cooling on a forward side wall of the pressure side and suction side tip rails to form a vortex flow of cooling air; and

,

discharging the cooling air from the suction side wall cooling out through the tip rails to produce air jets to block on-coming leakage flow across the blade tip.

19. The process for cooling and sealing a tip region of a turbine rotor blade of claim 18, and further comprising the step of:

passing the cooling air to the suction side tip rail vortex flow through the tip floor to provide cooling for the tip floor.

20. The process for cooling and sealing a tip region of a turbine rotor blade of claim 19, and further comprising the step of:

alternating passing the cooling air to the pressure side tip rail air jets through the tip floor with the passing of the cooling air from the suction side tip rail vortex flow to provide cooling for the tip floor.

21. The process for cooling and sealing a tip region of a turbine rotor blade of claim 18, and further comprising the step of:

passing the cooling air to the pressure side tip rail air jets through the tip floor to provide cooling for the tip floor.

22. The process for cooling and sealing a tip region of a turbine rotor blade of claim 18, and further comprising the steps of:

metering cooling air into a cooling supply cavity formed between the pressure side wall and the suction side wall; and

,

discharging a layer of film cooling air onto the leading edge region of the airfoil from the cooling supply cavity.

23. The process for cooling and sealing a tip region of a turbine rotor blade of claim 18, and further comprising the steps of:

metering cooling air into a cooling supply cavity formed between the pressure side wall and the suction side wall; and

,

cooling the trailing edge region of the airfoil with the cooling air from the cooling supply cavity.