Sealing Assembly for a Turbomachine

Abstract

A sealing assembly (23) for a turbomachine (1) having a seal carrier (24) and a seal structure (30) configured on the seal carrier (24), the seal structure (30) having additively built-up projections (32) that extend in each case away from the seal carrier (24) to a free end (32.1), the projections (32) being constructed in each case to have a varying cross-sectional profile, namely a particular projection (32) in a section (33) that is distal to the seal carrier (24) having a smaller thickness (34) at the free end (32.1) than in a section (35) that is proximal to the seal carrier (24).

Claims

1-15. (canceled)

16. A sealing assembly for a turbomachine comprising: a seal carrier; and a seal structure configured on the seal carrier, the seal structure having additively built-up projections extending in each case away from seal carrier to a free end, the projections each being constructed to have a varying cross-sectional profile, namely a respective projection of the projections having a smaller thickness at the free end in a distal section distal from seal carrier than in a proximal section proximal to the seal carrier.

17. The sealing assembly as recited in claim 16 wherein the thickness of the respective projection in the distal section is constant.

18. The sealing assembly as recited in claim 16 wherein the thickness of the respective projection in the distal section is at least 50 m and not more than 250 m.

19. The sealing assembly as recited in claim 16 wherein the respective projection has a maximum thickness in the proximal section corresponding to at least three times the average thickness in the distal section.

20. The sealing assembly as recited in claim 16 wherein the proximal section extends over at least and at most of a height taken toward the free end of the respective projection.

21. The sealing assembly as recited in claim 16 wherein the respective projection has a height of at least 2 mm and of at most 6 mm taken from the free end.

22. The sealing assembly as recited in claim 16 wherein, via a fillet composed of a plurality of radii, the respective projection runs into the seal carrier.

23. The sealing assembly as recited in claim 16 wherein the projections are struts, and the seal structure also has a filler material, the struts being embedded in the filler material and holding the same on the seal carrier.

24. The sealing assembly as recited in claim 16 wherein the projections are web walls, together, defining cavities open in each case to a side opposite the seal carrier.

25. The sealing assembly as recited in claim 24 wherein the web walls are each solid bodies, thus each extend continuously without discontinuity between the mutually opposing outer wall surfaces thereof.

26. A module for a turbomachine comprising the sealing assembly as recited in claim 16 and a sealing part moving during operation relative thereto.

27. The module as recited in claim 26 wherein the module radially defines a gas duct of the turbomachine, the sealing assembly being configured radially inside of the gas duct.

28. The module as recited in claim 26 wherein the sealing assembly is suspended radially within an inner platform of a guide vane ring of the module and positionally fixed relative to the guide vane ring, the sealing part being positionally fixed relative to a rotor blade ring of the module.

29. A turbomachine comprising the sealing assembly as recited in claim 16.

30. A jet engine comprising the sealing assembly as recited in claim 16.

31. A method for manufacturing the sealing assembly as recited in claim 16, wherein the projections of the seal structure are built-up additively.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention is explained in greater detail in the following with reference to an exemplary embodiment; within the scope of the coordinated independent claims, the individual features possibly being essential to the present invention in other combinations as well, and, as above, no distinction being specifically made among the different claim categories.

[0026] In the drawing,

[0027] FIG. 1 shows an axial cross-sectional view of a jet engine;

[0028] FIG. 2 shows a cut-away portion of a module of the jet engine, namely an inner air seal;

[0029] FIG. 3 shows a detail view of a seal structure as part of the inner air seal;

[0030] FIG. 4a-e show various options for designing the cavities including a seal structure having web walls;

[0031] FIG. 5 shows a seal structure constructed from struts.

DETAILED DESCRIPTION

[0032] In a schematic, axial cross-sectional view (relative to a longitudinal axis 2), FIG. 1 shows a turbomachine 1, specifically a turbofan engine. Turbomachine 1 is functionally divided into a compressor 1a, a combustion chamber 1b and a turbine 1c. Both compressor 1a and turbine 1c are thereby made up of a plurality of stages in each case; each stage is composed of a guide vane ring and rotor blade ring. Upstream of combustion chamber 1b, the intake air is compressed in a compressor gas duct 3.1; the expansion taking place in downstream hot gas duct 3.2.

[0033] FIG. 2 illustrates a cut-away portion of a module 20, which, in this form, may be provided both in compressor 1a, as well as in turbine 1c. Discernible is a guide vane 21, which has an inner platform 22 and is configured in gas duct 3. Extending radially inwardly from inner platform 22 is a pin 22.1 which is used to assemble a sealing assembly 23 in the form of what is commonly known as spoke centering. Pin 22.1 and a seal carrier 24 of sealing assembly 23 may be riveted to one another, for example. Also discernible are respective inner platforms 26.1, 26.2 of the upstream, respectively downstream rotor blade ring.

[0034] Particularly of interest in the present case is the design of a seal structure 30, which is configured radially inwardly on seal carrier 24 and against which sealing parts 31, which rotate during operation, namely sealing tips (fins) seal. Seal structure 30 is constructed from projections 32, which are built-up additively together with seal carrier 24. The manufacturing is carried out here in a powder bed process, the build-up direction being radially inward, thus downward in FIG. 2.

[0035] FIG. 3 shows two projections 32 in a schematic sectional view (rotated by 180 relative to FIG. 2). In a distal section 33 at free ends 32.1 of projections 32, respective thickness 34 thereof is about 150 m in each instance. Distal section 33 extends over of a height 36 of projections 32. In proximal section 35 that is contiguous thereto and disposed toward seal carrier 24, thickness 34 increases to about 500 m. The thicker proximal section 35 provides a good mechanical attachment; on the other hand, distal section 33 serves as an abradable portion into which the sealing tips may run.

[0036] Projections 32 may be formed as web walls; thus, relative to FIG. 3, they extend in elongated form upstream and downstream of the cross-sectional plane. FIG. 4a-e show such variants, in each case in a plan view, thus, from radially inwardly relative to the configuration in accordance with FIG. 2. Discernible, on the one hand, are web walls 40 and, on the other hand, radially inwardly open cavities 41 defined by the same. In the variant in accordance with FIG. 4a, web walls 40 form regular hexagons, thus a conventional honeycomb pattern. FIG. 4b-e illustrate the options that are made possible by additive manufacturing; a variation of the honeycomb form is possible (FIG. 4b); likewise possible are also other regular geometries (FIG. 4c, d) or even completely irregular configurations (FIG. 4e).

[0037] FIG. 5 shows a variant where projections 32 are pin-shaped struts 50. Struts 50 hold a filler material 51, namely polymer material as a run-in coating on seal carrier 24. Abrasion therefrom may take place during the run-in process in an area opposite seal carrier 24, together with distal sections 33 of struts 50.

LIST OF REFERENCE NUMERALS

[0038] turbomachine 1 [0039] compressor 1a [0040] combustion chamber 1b [0041] turbine 1c [0042] longitudinal axis 2 [0043] gas duct 3 [0044] compressor gas duct 3.1 [0045] hot gas duct 3.2 [0046] module 20 [0047] guide vane 21 [0048] inner platform 22 [0049] pin 22.1 [0050] sealing configuration 23 [0051] seal carrier 24 [0052] inner platform 26.1, 26.2 [0053] seal structure 30 [0054] sealing part (sealing tip) 31 [0055] projections 32 [0056] free ends 32.1 [0057] distal section 33 [0058] thickness 34 [0059] proximal section 35 [0060] height 36 [0061] web walls 40 [0062] cavities 41 [0063] struts or struts 50 [0064] filler material 51