Blade outer seal with micro axial flow cooling system

• US 20060140753A1
• Filed: 12/29/2004
• Published: 06/29/2006
• Est. Priority Date: 12/29/2004
• Status: Active Grant

• Current Assignee: Rtx Corporation
• Original Assignee: United Technologies Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Romanov, Dmitriy, Drake, Jeremy
• Granted Patent: US 7,306,424 B2
• Time in Patent Office: Days
• US Class Current: 415/173.100
• CPC Class Codes: F01D 11/08 for sealing space between rotor blade tips and stator specially-shaped blade tips therefor F01D5/20
• CPC Class Codes: F01D 25/12 Cooling
• CPC Class Codes: F05D 2240/11 Shroud seal segments
• CPC Class Codes: F05D 2260/2212 by creating turbulence vortex generators, turbulators or the like for mixing F05D2240/127
• CPC Class Codes: F05D 2260/2214 by increasing the heat transfer surface
• CPC Class Codes: F05D 2260/22141 using fins or ribs

Abstract

A turbine blade outer air seal assembly includes a hot side exposed to a combustion hot gas flow, and a back side that is exposed to a supply of cooling air. The outer air seal segment includes a trailing edge cavity and a leading edge cavity separated by a divider. The cavities are feed cooling air through a plurality of inlet openings disposed transverse to the gas flow. The cooling air enters the cavities and flows toward a plurality of outlets at the leading edge and a plurality of outlets along the trailing edge. A plurality of pedestals within each of the cavities disrupts cooling air flow to increase heat absorption capacity and to increase the surface area capable of transferring heat from the hot side.

Claims

1. A blade outer air seal assembly for a turbine engine comprising:

a cavity including a top surface and a bottom surface, said top surface comprising a side opposite a back side, and said bottom surface comprising a side opposite a hot side exposed to combustion gases; and

a plurality of pedestals extending between said top surface and said bottom surface for creating turbulent cooling air flow through said cavity.

2. The assembly as recited in claim 1, wherein said blade outer seal assembly includes a leading edge, a trailing edge, two axial edges and a plurality of inlet openings in said back side for providing cooling air flow into said cavity.

3. The assembly as recited in claim 2, wherein said plurality of inlet openings are arranged in a row substantially parallel with said leading edge and said trailing edge.

4. The assembly as recited in claim 3, wherein said plurality of inlet openings are arranged substantially midway between said leading edge and said trailing edge.

5. The assembly as recited in claim 3, wherein said cavity includes a divider for separating cooling air flow from said inlet holes such that a portion of said cooling air flow flows toward said leading edge and another portion flows toward said trailing edge.

6. The assembly as recited in claim 5, wherein said cavity comprises a leading edge cavity and a trailing edge cavity isolated from each other by said divider, wherein a cooling capacity of said cooling air flow corresponds to heat input such that said seal assembly maintains a desired surface temperature.

7. The assembly as recited in claim 3, including a plurality of outlets disposed at said leading edge and said trailing edge for exhausting cooling air flow into the flow of combustion gases.

8. The assembly as recited in claim 3, wherein said plurality of pedestals comprises a first plurality of pedestals arranged between said divider and said leading edge and second plurality of pedestals arranged between said divider and said trailing edge.

9. The assembly as recited in claim 8, including a third and a forth plurality of pedestals disposed along respective axial edges.

10. The assembly as recited in claim 9, wherein each of said third and fourth plurality of pedestals are isolated from any other of said pluralities of pedestals by an axial divider.

11. The assembly as recited in claim 1, wherein each of said plurality of pedestals comprises a cylindrical member.

12. The assembly as recited in claim 1, wherein each of said plurality of pedestals comprises a chevron shaped structure.

13. The assembly as recited in claim 1, wherein each of said plurality of pedestals comprises a rectangular structure.

14. The assembly as recited in claim 1, wherein each of said plurality of pedestals comprises an oval-shaped structure.

15. The assembly as recited in claim 1, wherein said plurality or pedestals comprise a tortuous path for cooling air flow.

16. A turbine blade shroud assembly for a turbine engine comprising:

a plurality of interfitting blade outer air seal segments, each of said plurality of interfitting blade outer air seal assemblies comprising a cavity including a top surface and a bottom surface, said top surface comprising a side opposite a back side, and said bottom surface comprising a side opposite a hot side exposed to combustion gases, and a plurality of pedestals extending between said top surface and said bottom surface for creating turbulent cooling air flow through said cavity.

17. The assembly as recited in claim 16, including an axial joint between adjacent ones of said plurality of interfitting blade outer air seal segments.

18. The assembly as recited in claim 16, wherein each of said plurality of outer air seal segments include a leading edge, a trailing edge, axial edges and a plurality of inlet openings disposed along said back side between said leading and trailing edges.

19. The assembly as recited in claim 18, wherein said cavity comprises a leading edge cavity and a trailing edge cavity separated by a divider.

20. The assembly as recited in claim 19, wherein said inlet openings are disposed to inject cooling air flow at an axial location with a greatest heat generation.