US-12618334-B2 - Stator vane assembly of a turbomachine and method for assembling a stator vane assembly

Abstract

A stator vane assembly ( 10 ) and a method for assembling a stator vane assembly ( 10 ) of a turbomachine, the stator vane assembly ( 10 ) including a plurality of variable stator vanes ( 11 ) whose stator vane platform ( 12 ) has a stator vane trunnion ( 13 ) that is mounted in a receiving opening ( 14 ) of a casing ( 15 ) of the turbomachine; a stator vane head ( 16 ) of the stator vane ( 11 ) having a bearing trunnion that is mounted on an inner ring ( 19 ) disposed on a rotor ( 119 ) of the turbomachine. In the method, a stator vane trunnion ( 13 ) disposed on a stator vane platform ( 12 ) of a stator vane ( 11 ) is inserted into a receiving opening ( 14 ) of a casing ( 15 ), which receiving opening ( 14 ) is disposed radially with respect to a rotor axis of the turbomachine, and an inner ring ( 19 ) is provided on a rotor ( 119 ) of the turbomachine.

Inventors

• Alexander Rauschmeier
• Christian Roth
• Thomas Stiftner
• Ralf Huber

Assignees

• MTU Aero Engines AG

Dates

Publication Date

20260505

Application Date

20240807

Priority Date

20230808

Claims (19)

1. 1 . A stator vane assembly of a turbomachine, the stator vane assembly comprising: a plurality of variable stator vanes, each stator vane having: a stator vane platform having a stator vane trunnion mounted in a receiving opening of a casing of the turbomachine, and a stator vane head having a bearing trunnion mounted on an inner ring configured to engage with a rotor of the turbomachine; and a respective support device for supporting each stator vane radially against the casing with respect to a rotor axis of the turbomachine, the respective support device disposed in the receiving opening and including, at least one first support element and at least one second support element, the second support element supporting the first support element radially against the casing within the receiving opening with respect to the rotor axis of the turbomachine.
2. 2 . The stator vane assembly as recited in claim 1 wherein the inner ring is a single piece or segmented.
3. 3 . The stator vane assembly as recited in claim 1 wherein the support device is configured to center a pitch change axis of the stator vane in the receiving opening.
4. 4 . The stator vane assembly as recited in claim 1 wherein the receiving opening is circular in shape at a radially inner end portion having a diameter equal to a diameter of the stator vane platform.
5. 5 . The stator vane assembly as recited in claim 1 wherein at least two adjacent receiving openings are interconnected at radially inner portions by a connecting opening in such a way that a portion of the stator vane is receivable in the connecting opening.
6. 6 . The stator vane assembly as recited in claim 1 wherein the respective support device is configured to support at least one rotary bearing bush for the stator vane.
7. 7 . The stator vane assembly as recited in claim 1 wherein the respective support device is locked in position in the receiving opening of the casing by a securing element.
8. 8 . The stator vane assembly as recited in claim 1 wherein the stator vane trunnion has a mounting groove in a portion opposite the stator vane platform.
9. 9 . The stator vane assembly as recited in claim 1 wherein the second support element is a slide bushing for the stator vane trunnion.
10. 10 . The stator vane assembly as recited in claim 1 wherein the first support element has at least one spacer element configured to support at least one hat bushing for the stator vane platform.
11. 11 . The stator vane assembly as recited in claim 1 wherein the first support element is a sleeve element configured to at least partially embrace the stator vane trunnion.
12. 12 . The stator vane assembly as recited in claim 11 wherein the sleeve element is configured to support two rotary bearing bushes with respect to the stator vane.
13. 13 . The stator vane assembly as recited in claim 11 wherein the second support element is locked in position in the receiving opening of the casing by a retainer.
14. 14 . The stator vane assembly as recited in claim 1 wherein the inner ring is configured as a half-ring.
15. 15 . The stator vane assembly as recited in claim 1 wherein the first support element includes a hat bushing.
16. 16 . The stator vane assembly as recited in claim 15 wherein the first support element has a spacer ring spacing the hat bushing from the second support element.
17. 17 . The stator vane assembly as recited in claim 15 wherein the second support element includes a slide bushing and the hat bushing has a maximum outer diameter larger than that of the slide bushing.
18. 18 . The stator vane assembly as recited in claim 17 wherein the first support element has a spacer ring spacing the hat bushing from the slide bushing, the spacer ring having a same maximum outer diameter as that of the hat bushing.
19. 19 . A turbomachine comprising at least one stator vane assembly as recited in claim 1 .

Description

This claims priority to German Patent Application 102023121106.4, filed on Aug. 8, 2023, which is hereby incorporated by reference herein. The invention relates to a stator vane assembly of a turbomachine including a plurality of variable stator vanes whose stator vane platform has a stator vane trunnion that is mounted in a receiving opening of a casing of the turbomachine, and further relates to a method for assembling a stator vane assembly. BACKGROUND A turbomachine includes, in serial flow arrangement, a compressor, a combustor, and a turbine. Air enters the turbomachine and is pressurized in the compressor. The compressed air is then mixed with fuel in the combustor. Hot combustion gases are produced when the mixture of compressed air and fuel is subsequently burned in the combustor. The hot combustion gases flow downstream to the turbine, which extracts energy from the combustion gases to drive the compressor. SUMMARY OF THE INVENTION Both the compressor and the turbine of a turbomachine usually include a plurality of stages, each stage having a row of stationary stator vanes and a row of rotating rotor blades. The stationary stator vanes direct the gas flow in such a way that it meets the rotating rotor blades at a predetermined angle. The stator vanes may be rotatable about their longitudinal axes to permit adjustment of the angle of attack. Such stator vanes are typically mounted at their radially inner ends on a stationary inner ring, whereby spoke-type centering of the assembly is provided. This creates a degree of freedom of the inner ring relative to the rotor of the turbomachine, whereby a necessary play is created between these components of the turbomachine. The radially outer ends of the variable stator vanes are usually mounted on the casing of the turbomachine so as to be rotatable about their, in particular radially oriented, longitudinal axes. Since typically a plurality of components are mounted on the inner ring in a narrow installation space, complex inner ring designs are sometimes required, which impair the stability and/or inherent stiffness of the inner ring and thus also the continuity of a sealing gap of the turbomachine. In view of the above, it is an object of the present invention to provide an improved stator vane assembly of a turbomachine as well as an improved turbomachine. Another object is to provide an improved method for assembling a stator vane assembly and for assembling a flow assembly of a turbomachine. This is achieved in accordance with the invention by the teaching of the independent claims. Advantageous embodiments of the invention are the subject matter of the dependent claims. The present invention provides a stator vane assembly of a turbomachine, the stator vane assembly including a plurality of variable stator vanes. The stator vane platform of a stator vane has a stator vane trunnion, which is mounted in a receiving opening of a casing of the turbomachine, which receiving opening is disposed in particular radially with respect to a rotor axis of the turbomachine. A stator vane head of the stator vane has a bearing trunnion, which is mounted on an inner ring disposed on a rotor of the turbomachine. Each stator vane is supported against the casing by means of a respective support device disposed in the receiving opening. The support device includes at least one first support element and at least one second support element, the second support element supporting the first support element within the receiving opening on the casing radially with respect to a rotor axis of the turbomachine. The support device reduces, in particular prevents, relative movement of the stator vanes with respect to the casing, in particular in a longitudinal direction of the stator vane, and in particular of a plurality of stator vanes with respect to one another. This makes it possible to reduce load placed on the inner ring as a result of relative movement of the stator vane(s), which firstly allows for a simplified design of the inner ring and secondly facilitates the assembly of the stator vane assembly due to a simplified design of the inner ring. The support elements may be configured and/or disposed in the receiving opening in such a way that they form a support device or support the stator vanes against the casing. For example, the first support element and the second support element may be configured or interact in such a way that they, in particular each, surround the stator vane trunnion radially at least partially, in particular completely. The first support element and the second support element may rest against each other. In particular, both support elements are designed to rest against the casing, i.e., against the inner periphery of the receiving opening, also in the axial direction and/or in the circumferential direction so as to support the stator vane or the stator vane trunnion and/or the stator vane platform. The support elements may be insertable into the r