Stacked lamellate assembly

• US 20060120874A1
• Filed: 01/07/2005
• Published: 06/08/2006
• Est. Priority Date: 12/02/2004
• Status: Active Grant

• Current Assignee: Siemens Energy Incorporated (Siemens AG)
• Original Assignee: Siemens Westinghouse Power Corporation
• Inventors: Morrison, Jay A., Parthasarathy, Vijay, Merrill, Gary B., Keller, Douglas Allen, Vance, Steven James, Thompson, Daniel G., Burke, Michael A.
• Granted Patent: US 7,247,003 B2
• Time in Patent Office: Days
• US Class Current: 416/229.R
• CPC Class Codes: F01D 5/147 Construction, i.e. structural features, e.g. of weight-saving hollow blades F01D5/148, F01D5/16 and F01D5/20 take precedence; blade shape F01D5/141; blades with cooling or heating channels or cavities F01D5/18; heating, heat-insulating or cooling means on blades F01D5/18
• CPC Class Codes: F01D 5/282 Selecting composite materials, e.g. blades with reinforcing filaments
• CPC Class Codes: F01D 5/284 Selection of ceramic materials
• CPC Class Codes: F04D 29/388 characterised by construction
• CPC Class Codes: F05D 2230/23 by permanently joining parts together
• CPC Class Codes: F05D 2300/601 Fabrics
• CPC Class Codes: F05D 2300/603 Composites; e.g. fibre-reinforced
• CPC Class Codes: F05D 2300/614 Fibres or filaments

Abstract

A stacked ceramic matrix composite lamellate assembly (10) including shear force bearing structures (48) for resisting relative sliding movement between adjacent lamellae. The shear force bearing structures may take the form of a cross-lamellar stitch (50), a shear pin (62), a warp (90) in the lamellae, a tongue (104) and groove (98) structure, or an inter-lamellar sealing member (112), in various embodiments. Each shear force bearing structure secures a subset of the lamellae, with at least one lamella being common between adjacent subsets in order to secure the entire assembly.

Claims

1. A lamellate airfoil assembly comprising:

a stacked plurality of ceramic matrix composite lamellae each comprising a peripheral surface collectively defining an airfoil shape;

a fastener applying a compressive pre-load to the stacked lamellae in a through thickness direction; and

a plurality of shear force bearing structures separate from the fastener and disposed to resist sliding movement in an in-plane direction between adjacent ones of the lamellae, each shear force bearing structure in contact with a respective subset of the plurality of lamellae, with at least one lamella of each subset being part of another subset so that collectively the plurality of shear force bearing structures secure all of the lamellae against relative sliding movement.

2. The airfoil assembly of claim 1, wherein the shear force bearing structure comprises a stitch interconnecting the adjacent ones of the lamellae.

3. The airfoil assembly of claim 1, wherein the shear force bearing structure comprises a shear pin extending in the through thickness direction between the adjacent ones of the lamellae.

4. The airfoil assembly of claim 3, wherein the shear pin comprises a hollow tube.

5. The airfoil assembly of claim 3, wherein the shear pin comprises a fiber bundle.

6. The airfoil assembly of claim 3, wherein the shear pin comprises a ceramic matrix composite material.

7. The airfoil assembly of claim 3, wherein the shear pin comprises a clamp comprising a central web portion extending in the through thickness direction between the two adjacent ones of the lamellae and a flange portion at each opposed end of the web portion extending over the respective adjacent one of the lamellae.

8. The airfoil assembly of claim 1, wherein the shear force bearing structures comprise a ceramic fiber rope comprising a central web portion and opposed flange portions comprising splayed out fibers of the rope on opposed ends of the central web portion.

9. The airfoil assembly of claim 1, wherein the shear force bearing structure comprises a warp formed in each of the adjacent ones of the lamella.

10. The airfoil assembly of claim 9, wherein the warp of each lamella comprises a double curvature saddle surface shape.

11. The airfoil assembly of claim 1, further comprising:

a groove formed in a first of the adjacent ones of the lamellae;

a tongue formed in a second of the adjacent ones of the lamellae opposed the groove, the tongue and groove cooperating to resist the sliding movement.

12. The airfoil assembly of claim 1, further comprising:

a first groove formed in a first of the adjacent ones of the lamellae;

a second groove formed in a second of the adjacent ones of the lamellae adjoining the first of the lamellae;

a sealing member disposed in a space defined by the first groove and the second groove.

13. The airfoil assembly of claim 12, wherein the sealing member comprises a rope seal.

14. A lamellate assembly comprising:

a stacked plurality of lamellae each comprising an anisotropic ceramic matrix composite material exhibiting an in-plane tensile strength substantially greater than a through thickness tensile strength; and

a means for resisting relative sliding movement associated with each of a plurality of subsets of the lamellae.

15. The lamellate assembly of claim 14, wherein the means for resisting relative sliding movement comprises a stitch interconnecting the at least two adjacent ones of the lamellae.

16. The lamellate assembly of claim 14, wherein the means for resisting relative sliding movement comprises a shear pin extending in the through thickness direction between at least two adjacent ones of the lamellae.

17. The lamellate assembly of claim 16, wherein the shear pin comprises a hollow tube.

18. The lamellate assembly of claim 16, wherein the shear pin comprises a fiber bundle.

19. The lamellate assembly of claim 16, wherein the shear pin comprises a ceramic matrix composite material.

20. The lamellate assembly of claim 16, wherein the shear pin comprises a clamp comprising a central tubular portion extending in the through thickness direction between the at least two adjacent ones of the lamellae and a flange portion at each opposed end of the tubular portion extending over a respective one of the at least two adjacent ones of the lamellae.

21. The lamellate assembly of claim 14, wherein the means for resisting relative sliding movement comprises a ceramic fiber rope comprising a central web portion extending through adjacent lamellae and opposed flange portions comprising splayed out fibers of the rope on opposed ends of the central web portion.

22. The lamellate assembly of claim 14, wherein the means for resisting relative sliding movement comprises a respective warp formed in each of two adjacent lamellae.

23. The lamellate assembly of claim 22, wherein the warp of each lamella comprises a double curvature saddle surface shape.

24. The lamellate assembly of claim 14, further comprising:

a groove formed in a first lamella;

a tongue formed in a second lamella opposed the groove, the tongue and groove cooperating to resist the sliding movement.

25. The airfoil assembly of claim 14, further comprising:

a first groove formed in a first lamella;

a second groove formed in a second lamella adjoining the first lamella;

a sealing member disposed in a space defined by the first groove and the second groove.

26. The airfoil assembly of claim 25, wherein the sealing member comprises a rope seal.

27. A lamellate airfoil assembly comprising:

a stacked plurality of ceramic matrix composite lamellae each comprising an anisotropic ceramic matrix composite material exhibiting an in-plane tensile strength substantially greater than a through thickness tensile strength and each comprising a peripheral surface collectively defining an airfoil shape;

a fastener applying a compressive pre-load to the stacked lamellae in a through thickness direction;

a plurality of shear force bearing structures separate from the fastener, each shear force bearing structure extending in the through thickness direction through adjacent ones of a respective subset of the lamellae; and

each subset comprising at least one lamella in common with another subset so that collectively the plurality of shear force bearing structures secure all of the lamellae against relative sliding movement.