Guide vane assembly with sealing element and gas turbine engine

Abstract

Guide vane assembly for a drive unit (T), comprising at least one guide vane (111) of a guide vane row (13a-13c) and a housing (1) for the at least one guide vane row (13a-13c), wherein the at least one guide vane (111) is adjustably mounted on the housing (1) via a bearing journal (111a), which is rotatably mounted in a bearing opening (O) in the housing (1) and extends through this bearing opening (O) along a longitudinal axis (L), wherein a section (40) of a sealing element (4, 5, 6) is provided within the bearing opening (O), on which at least one sealing rib (400, 500) extending radially with respect to the longitudinal axis (L) is formed and / or which has a non-linearly extending slot (401, 601) traversing the section (40) longitudinally, characterized in that (a) the at least one radially extending sealing rib (400, 500) extends into a recess (111.4, 111.5) of the bearing journal (111a) or (b) at least two successive sealing ribs (400, 500) are formed on the section (40) provided within the bearing opening (O) and the section formed with the at least two radially extending sealing ribs (400, 500) is received in a recess (111.4, 111.5) of the bearing journal (111a) and the at least two sealing ribs (400, 500) extend radially outwards in the direction of an inner surface (100) of the bearing opening (10).

Description

[0001] The proposed solution concerns a guide vane assembly for an engine and a gas turbine engine.

[0002] It is well known that variable stator vanes are used in engines, such as turbomachines and especially gas turbine engines, to influence the flow depending on the speed and outside temperature of rotating blades. In gas turbine engines in particular, variable stator vanes are commonly used in the compressor area, with the vanes being adjusted depending on the compressor speed. These variable stator vanes are referred to as variable stator vanes (VSVs) in technical terms.

[0003] The adjustable guide vanes are usually part of a row of guide vanes and arranged within a casing in which the rotating rotor blades are also arranged. In practice, the individual guide vanes are each adjustably mounted on the casing via a bearing journal. Within the casing, a rotatable bearing for a guide vane is usually provided on a hub, e.g. of a compressor. On the casing, each bearing journal is rotatably mounted in a corresponding bearing opening in the wall of the casing. The bearing journal passes through this bearing opening along a longitudinal axis such that one end of the bearing journal is accessible on an outer side of the casing, so that the corresponding guide vane can be adjusted by rotating the bearing journal.Typically, a lever engages each pin end, which is attached to an adjusting ring of an adjusting mechanism, in order to simultaneously adjust several guide vanes by adjusting the adjusting ring and several levers hinged thereto. Such a generic guide vane assembly with adjustable guide vanes for a compressor of a gas turbine engine is shown, for example, in DE 10 2016 215 807 A1, US 6,086,327 A, US 9,309,778 B2, or DE 693 00 297 T2.

[0004] The guide vane journals, often referred to as spindles, are typically located in radially protruding, sleeve-shaped bearing extensions on the casing. These bearing extensions are formed on a casing wall and ensure the rotatable mounting and support of the bearing journals.

[0005] In practice, due to the intended component tolerances, wear during operation, and the need to provide a gap between the bearing journal and, for example, a bearing bush that rotatably supports the journal in the bearing opening, a leakage flow to the outside occurs through the bearing opening. This leakage flow reduces the mass flow in the core engine.

[0006] It is therefore the task of the proposed solution to provide improved guide vane assembly in this respect.

[0007] This object is achieved with a guide vane assembly of claim 1.

[0008] Accordingly, a guide vane assembly for an engine is proposed, comprising at least one guide vane of a guide vane row and a housing for the at least one guide vane row. The at least one guide vane is adjustably mounted on the housing via a bearing pin, which is rotatably mounted in a bearing opening in the housing and extends through this bearing opening along a longitudinal axis. Within the bearing opening, a section of a sealing element is provided, on which at least one sealing web is formed, extending radially with respect to the longitudinal axis, and / or which has a non-linear slot traversing the section longitudinally.

[0009] According to the proposed solution, a sealing element is provided for sealing the bearing opening with the bearing journal adjustably mounted therein, which sealing element is designed according to two different, but combinable, aspects. Firstly, the sealing element can have a section on which at least one sealing web is formed, extending radially with respect to the longitudinal axis, in order to reduce or prevent leakage flow along the bearing journal through the bearing opening to the outside. Secondly, the sealing element can have a slot that extends longitudinally through the section of the sealing element provided within the bearing opening, in particular to facilitate assembly and to allow temperature-related expandability of the sealing element along the circumferential direction and in the radial direction.This slot does not run linearly and thus parallel to the longitudinal axis of the bearing opening, but rather has a non-linear profile, which prevents or at least significantly reduces leakage flow across the slot. By providing at least one radially projecting sealing ridge and the non-linear slot on a sealing element, a type of labyrinth seal can be created along the longitudinal axis of the bearing journal within the bearing opening.

[0010] For example, it is provided that the section of the sealing element provided within the bearing opening forms a labyrinth seal to reduce or prevent leakage flow through the bearing opening and along the bearing journal. This labyrinth seal can be (co-)defined by the at least one radially extending sealing ridge and / or the non-linear slot within the sealing element, as explained above. A longitudinally slotted sealing element enables installation on the bearing journal of the guide vane, even with a one-piece design of the sealing element, by widening the sealing element. Alternatively, a two-part sealing element (in particular with at least one radially extending sealing ridge) can be provided to facilitate installation on the bearing journal or guide vane, or even to enable it in the first place.

[0011] In a two-part or generally multi-part design of the sealing element, the at least one non-linear slot extending longitudinally through the sealing element can separate two parts of the sealing element, e.g., two halves of a bush-shaped sealing element. Two parts of the sealing element thus adjoin one another along the slot. In particular, due to the non-linear shape of the slot on the assembled sealing element, sections of two parts of a multi-part sealing element can overlap.

[0012] In one embodiment, the at least one radially extending sealing ridge of a section of the sealing element provided within the bearing opening has a taper in the direction of the bearing journal on at least one ridge section. Such a taper can be wedge-shaped or arrow-shaped, for example. The taper at the end of the radially extending sealing ridge forms a type of narrow sealing lip, which can be in frictional contact with the adjustable bearing journal.

[0013] According to a first aspect of the proposed solution, the at least one radially extending sealing ridge extends into a recess in the bearing journal. A radially recessed section is thus provided on the bearing journal, thus forming a depression, recess, or gap in the bearing journal. The radially extending sealing ridge then extends into this radially recessed section. Viewed along the longitudinal axis of the bearing journal, any air flow is thus deflected several times along the longitudinal axis, effectively reducing or even preventing any significant leakage flow through the bearing opening.

[0014] In principle, with a sealing web extending radially into a recess in the bearing journal, the at least one sealing web can have an end region that frictionally engages an outer surface of the bearing journal and is intended to be at least partially abraded by the adjustment of the bearing journal about the longitudinal axis during operation of the engine. Consequently, in this variant, the sealing element with the radially extending sealing web is designed such that the radially extending sealing web frictionally engages the outer surface of the bearing journal, and an optimal gap is created during operation of the engine, in which gap a portion of the adjacent end region of the sealing web is abraded by the adjustment of the bearing journal. Such an end region can then, for example, also have a tapered web section.

[0015] According to an alternative aspect of the proposed solution, at least two sealing webs are formed on the section of the sealing element provided within the bearing opening, one following the other along the longitudinal axis. For example, three or more, in one embodiment a maximum of five, radially extending sealing webs can be provided one following the other along the longitudinal axis within the bearing opening. In particular, two or more sealing webs can also be formed on the sealing element. If necessary, a further sealing element, likewise with at least one radially extending sealing web, is additionally provided within the bearing opening in order to provide at least three and / or a maximum of five radially extending sealing webs, one following the other along the longitudinal axis, within the bearing opening. The section formed with the at least two radially extending sealing webs is received in a recess in the bearing journal.The at least two sealing ridges then extend radially outward toward an inner circumferential surface of the bearing opening. The sealing ridge can thus also be frictionally engaged, but then against the inner circumferential surface of the bearing opening, if the sealing element is rotatably held together with the bearing journal within the bearing opening. Such a design variant of the sealing element, which is accommodated in a recess of the bearing journal, is suitable, for example, for a bush-shaped design of the sealing element and for arranging the sealing element in a central area within the bearing opening, so that no part of the sealing element protrudes from the bearing opening.

[0016] In addition to the section formed with the at least one radially extending sealing web, the sealing element can have a bearing section via which the sealing element bears against a radially inner edge surface of the housing—relative to a center axis of the guide vane row of the at least one guide vane—which borders the bearing opening. Such a bearing section is formed, for example, by a collar-shaped web or bushing edge that bears against the inner edge surface of the housing and from which a shaft section with the at least one sealing web extends into the bearing opening.

[0017] The bearing section of the sealing element, which rests against the edge surface, ensures a defined position of the sealing element relative to the bearing opening in a simple manner. If necessary, the sealing element can also be fixed to the edge surface of the housing via the bearing section, forming a seal against the edge surface. This prevents leakage from the interior of the housing to the outside via a gap between the sealing element and an inner surface of the bearing opening. For example, the bearing section can be sealingly connected to the inner edge surface of the housing by means of an adhesive.

[0018] In one embodiment, at least two sealing elements are provided, each of which has a section within the bearing opening, on which at least one sealing web is formed that extends radially relative to the longitudinal axis and / or which has a non-linear slot that traverses the section along its entire length. Thus, two separate sealing elements are provided for sealing the bearing opening and the guide vane bearing journal adjustably mounted therein. These sealing elements can thus be arranged at different positions along the longitudinal axis to effectively prevent leakage.

[0019] In principle, a sealing element can be bush-shaped or disc-shaped. This includes, in particular, the sealing element being designed as a sealing disc with or without a radially extending sealing ridge, but with a non-linear slot running longitudinally through the sealing disc.

[0020] The non-linear slot extending longitudinally through the section of the sealing element provided within the bearing opening can have a discontinuous shape in the mathematical sense. Thus, the non-linear and, in particular, discontinuous slot ensures that sections of the sealing element at least partially overlap each other axially and / or interlock in the circumferential direction. Thus, despite the possibility of assembly-related and temperature-related expansion, in particular widening of the sealing element, provided by the slot, leakage flow through the slot is avoided or at least significantly reduced.A flow arising within the slot would therefore be deflected at least once, possibly even at least twice, whereby the probability of flow through the slot is considerably reduced due to the prevailing pressure differences between an interior of the casing accommodating the row of guide vanes and an exterior space. Although the slot thus provides the possibility of expanding the sealing element during assembly, particularly in the section to be accommodated within the bearing opening, in order to be able to attach the sealing element to the bearing journal, and that the sealing element can readily expand if the sealing element is considerably heated during operation of the engine, the sealing effect of the sealing element along the longitudinal axis through the slot is not or hardly reduced due to the non-linear course of the slot.

[0021] In principle, the sealing element can be designed in such a way that the sealing element rests against the inner wall of the bearing opening, e.g. a housing bore, via an outer surface under the thermal conditions occurring during operation of the engine and thus seals. In particular, with an annular sealing element, thermal expansion can occur in the circumferential direction and radially inwards. If a recess is provided on the bearing journal in which the slotted sealing element is positioned, an overlap with the sealing element is created in the axial direction, which has a sealing effect, in particular a sealing effect under all (transient) thermal conditions. In this context, the longitudinal slot is designed accordingly to compensate for the thermal behavior and still provide additional sealing.

[0022] For example, the non-linear slot that crosses the section of the sealing element provided within the bearing opening has a helical, Z-, V- or Ω-shaped course.

[0023] The problem is also solved with a guide vane assembly of claim 11.

[0024] Accordingly, a guide vane assembly for an engine is proposed, comprising at least one guide vane of a guide vane row and a housing for the at least one guide vane row. The at least one guide vane is adjustably mounted on the housing via a bearing pin, which is rotatably mounted in a bearing opening in the housing and extends through this bearing opening along a longitudinal axis. A section of a sealing element is provided within the bearing opening, which has a non-linear slot traversing the section longitudinally.The sealing element has a sealing bushing and a sealing disc, wherein the sealing disc is received in a recess of the bearing journal, wherein a narrow gap is provided between an outer circumferential surface of the bearing journal in the region of the recess and an inner circumferential surface of the sealing disc to provide a labyrinth seal, while an outer circumferential surface of the sealing disc lies sealingly against an inner circumferential surface of the bearing opening.

[0025] The proposed solution also relates to a gas turbine engine with one of the proposed guide vane assemblies. In particular, a gas turbine engine can be provided with a guide vane assembly in which the bearing journals of all guide vanes are equipped with a sealing element designed as proposed within the respective bearing opening to prevent leakage.

[0026] The attached figures illustrate possible embodiments of the proposed solution.

[0027] Here we show: Fig. 1A shows a detail of a variant of a proposed guide vane assembly in the region of a bearing opening of a housing, wherein a bearing pin of a guide vane, which is rotatably held in the bearing opening, is provided via a bush-shaped sealing element with several (at least two) rows of radially extending sealing webs; Fig. 1B is a side view of the bushing-shaped sealing element, illustrating in particular a Z-shaped slot extending longitudinally through a shaft portion of the sealing element; Fig. 1C a plan view of the bush-shaped sealing element of the Fig. 1A and Fig. 1B; Fig. 2 shows a further embodiment of a proposed guide vane assembly in accordance with the Fig. 1A corresponding view, wherein two separate bush-shaped sealing elements are provided; Fig. 3 in with the Fig. 1A and Fig. 2 shows a corresponding view of a guide vane assembly with a bush-shaped sealing element, illustrating differently designed radially extending sealing webs; Fig. 4 in with the Fig. 1A, Fig. 2 and Fig. 3 shows a further embodiment of a proposed guide vane assembly with a disc-shaped, longitudinally slotted sealing element; Fig. 4A in section along a section line AA of the Fig. 4 the disc-shaped sealing element in individual view; Fig. 4B-4E along a line of sight B corresponding to the Fig. 4A shows a side view of the disc-shaped sealing element with V-, Z-, Ω- or helical shape of the slot in the disc-shaped sealing element; Fig. 5A-5C each show a longitudinal section of a further embodiment of a proposed guide vane assembly with different bush-shaped sealing elements, each having several rows of radially extending sealing webs; Fig. 5D-5F perspective, sectioned views of the bush-shaped sealing elements of the Fig. 5A, Fig. 5B and Fig. 5C; Fig. 6A-6B show a side view of a variant of a bush-shaped sealing element with a Z-shaped slot under two different thermal boundary conditions; Fig. 7 shows a schematic sectional view of a gas turbine engine in which at least one guide vane assembly according to the invention is used; Fig. 8 shows a partial and perspective view of an arrangement known from the prior art with several guide vane assemblies, each with a row of guide vanes and several rotor blade assemblies.

[0028] The Fig. Figure 7 illustrates schematically and in cross-section a (gas turbine) engine T in the form of a turbofan engine, in which the individual engine components are arranged one behind the other along a central axis or axis of rotation M. At an inlet or intake E of the engine T, air is sucked in along an inlet direction E by means of a fan F. This fan F is driven via a connecting shaft which is rotated by a turbine TT. The turbine TT is connected to a compressor V, which has, for example, a low-pressure compressor 11 and a high-pressure compressor 12, and possibly also a medium-pressure compressor. The fan F supplies air to the compressor V on the one hand and to a bypass duct B on the other hand to generate the thrust. The air conveyed via the compressor V finally reaches a combustion chamber section BK, in which the drive energy for driving the turbine TT is generated.For this purpose, the turbine TT comprises a high-pressure turbine 13, a medium-pressure turbine 14, and a low-pressure turbine 15. The turbine TT drives the fan F using the energy released during combustion, which then generates the required thrust via the air fed into the bypass duct B. The air exits the bypass duct B in the area of ​​an outlet A at the end of the engine T, where the exhaust gases from the turbine TT flow out. The outlet A typically has a thrust nozzle.

[0029] In principle, the fan F can also be coupled to and driven by the low-pressure turbine 15 via a connecting shaft and an epicyclic planetary gear. Furthermore, other, differently designed gas turbine engines can also be provided, to which the proposed solution can be applied. For example, such engines can have an alternative number of compressors and / or turbines and / or an alternative number of connecting shafts. As an example, the engine can have a split-flow nozzle, meaning that the flow through the bypass duct B has its own nozzle, separate from the engine core nozzle and located radially outward.However, this is not limiting, and any aspect of the present disclosure may also apply to engines in which the flow through bypass duct B and the flow through the core are mixed or combined before (or upstream of) a single nozzle, which may be referred to as a mixed-flow nozzle. One or both nozzles (whether mixed or split-flow) may have a fixed or variable area. Although the described example refers to a turbofan engine, the proposed solution may be applied to any type of gas turbine engine, such as an open-rotor (where the fan stage is not surrounded by an engine nacelle) or a turboprop engine.

[0030] In the variant of an engine T illustrated here as an example, the compressor V comprises several rows of rotor blades 110 arranged one behind the other in the axial direction and intermediate rows of guide vanes 111 in the region of the low-pressure compressor 11. The rows of rotor blades 110 rotating about the central axis M and the rows of stationary guide vanes 111 are arranged alternately along the central axis M and accommodated in a (compressor) housing 1 of the compressor V. The individual guide vanes 111 are adjustably mounted on the single-part or multi-part housing 1 - usually in addition to a radially inner bearing on the hub of the compressor V.

[0031] The Fig. Figure 8 shows a section in greater detail of an arrangement of rotor blade rows 12a to 12d and guide vane rows 13a to 13c for the low-pressure compressor 11, known from the prior art. The guide vanes 111 of the successively arranged guide vane rows 13a, 13b, and 13c are adjustably mounted on the casing 1 in order to be able to change the position of the guide vanes 111 depending on the compressor speed and inlet gas temperature. For this purpose, a bearing journal 111a of each rotor blade 111 is rotatably mounted in a bearing opening O, which is formed by a sleeve-shaped and radially outwardly projecting bearing extension 10 of the casing 1. Each bearing journal 111a is rotatably mounted and supported in an associated bearing extension 10. Each bearing pin 111a extends through its associated bearing extension 10 along a longitudinal axis L, so that a pin end 111b protrudes from the bearing extension 10 on the outside of the housing 1.

[0032] An adjusting lever 31 of an adjusting device 3 can thus engage each of the individual pin ends 111b in order to rotate the bearing pin 111a and thus change the position of the associated guide vane 111. The levers 31 of a guide vane row 13a, 13b or 13c are each articulated to an adjusting element in the form of an adjusting ring 30 of the adjusting device 3. The adjusting ring 30 - often multi-part, divided into at least two segments - extends circumferentially along the outer surface of the housing 1. By adjusting the adjusting ring 30, the adjusting levers 31 articulated thereto and several, usually all, guide vanes 111 of a guide vane row 13a, 13b or 13c can be adjusted. The individual adjusting rings 30 for the individual guide vane rows 13a, 13b and 13c are usually adjustable independently of one another.

[0033] Due to component tolerances, wear during operation of the engine T and the need to maintain a gap in the area of ​​the adjustable bearing journal 111a within the bearing opening O, in practice there is often an undesirable leakage flow from an annular space RR (in which the guide vane rows 13a-13d are arranged) inside the casing 1 to the outside, whereby the mass flow in the core engine may be reduced only slightly but not insignificantly.

[0034] In a Fig. In the embodiment of a proposed guide vane assembly shown in Figure 1A, such undesirable leakage flow is reduced or even completely avoided by an additional sealing element in the form of a sealing bushing 4. The sealing bushing 4 has a bearing section in the form of a collar-shaped bushing edge 41, via which the sealing bushing 4 bears against an inner edge surface 10b that is located radially inward relative to the central axis M and thus faces the annular space RR. From this bushing edge 41, a shaft section 40 extends into the interior of the bearing opening O, which in this case has several (at least two) rows of sealing webs 400 that protrude radially (relative to the longitudinal axis L) and encircle the longitudinal axis L.

[0035] The sealing webs 400 each protrude in the direction of the bearing journal 111a from an inner circumferential surface of the shaft section 40 and each extend with a tapered end region into a recess 111.4 of the bearing journal 111a.

[0036] In this case, a narrow gap g1 is provided between an inner circumferential surface 100 of the bearing extension 10 of the housing 1 in the bearing opening O and an outer circumferential surface of the shaft section 40. However, due to the sealing engagement of the bushing edge 41 with the inner edge surface 10b, outward flow through this gap g1 is prevented. Alternatively, a press fit can be provided for the shaft section 40.

[0037] For the rotatable mounting of the bearing journal 111a in the bearing opening O, a gap g2 still exists between the inner circumferential surface of the shaft section 40 and an outer circumferential surface of the bearing journal 111a. However, a labyrinth seal is formed here via the several rows of sealing webs 400 and the recesses 111.4 provided in the bearing journal 111a, which prevents leakage flow outward along the longitudinal axis L.

[0038] The sealing bushing 4 is designed in two parts with two bushing halves (or half-bushes) which are separated from each other by two longitudinal slots 401, so that the two bushing halves adjoin each other along the slots 401 in the assembled state. In a one-piece sealing bushing 4, the sealing bushing 4 is analogous to the individual representations of the Fig. 1B and Fig. 1C is longitudinally slotted to enable the sealing bushing 4 to be mounted on the bearing journal 111a. These slots 401 allow the sealing bushing 4 to be expanded for mounting on the bearing journal 111a. Furthermore, the slots 401 allow for temperature-induced expansion of the mounted sealing bushing 4, particularly in the area of ​​the shaft section 40.

[0039] In order to prevent the sealing effect of the sealing bushing 4 from being negatively influenced by the provision of the slots 401, each slot 401 has a non-linear, discontinuous course, so that circumferential sections 40a and 40b of the shaft section 40 belonging to different bushing halves axially overlap one another at least partially. In the embodiment of the Fig. 1A to 1C, the slot 401 is Z-shaped.

[0040] It should also be noted that the sealing bush 4 is provided at a radially inner end of the bearing opening O with respect to the central axis M, in addition to a bearing bush 2, via which the bearing journal 111a is rotatably mounted within the bearing opening O. This bearing bush 2 has a collar-shaped bushing edge, which is fixed to a radially outer edge surface 10a of the bearing extension 10 via an (optional) adhesive surface 20 on its underside. The bearing bush 2 is thus also sealingly fixed to the bearing extension 10 and thus only a gap exists between an inner circumferential surface of the bearing bush 2 and the outer circumferential surface of the bearing journal 111a.

[0041] In the version of the Fig. 2, in addition to the sealing bushing 4, an additional sealing element in the form of a further sealing bushing 5 is provided along the longitudinal axis L. This further sealing bushing 5 also has a plurality of sealing webs 500 circumferentially extending around the longitudinal axis L and projecting radially with respect to the longitudinal axis L. These sealing webs 500, which taper in the direction of the bearing journal 111a, also extend into additionally provided recesses 111.5 of the bearing journal 111a and thus define an additional labyrinth seal on the outer surface of the bearing journal 111a, spaced from the sealing bushing 4 and its sealing webs 400.

[0042] Instead of a bearing bush, the design variant of the Fig. 2, a bearing disc 2 is provided on the radially outer edge surface 10a. This bearing disc 2 is also fixed to the front edge surface 10b via an (optional) adhesive surface 20. Via the bearing disc 2 of the Fig. 2 thus only provides an axial bearing for the adjusting lever 31 (as with the bushing edge of the bearing bush 2), but no rotatable bearing for the bearing pin 111a. Therefore, only the sealing bushes 4 and 5 are provided for the rotatable bearing of the bearing pin 111a within the bearing opening O.

[0043] In the version of the Fig. 3, in addition to the bearing bush 2, only a single sealing element in the form of a sealing bush 4 with several rows of sealing ridges 400 is provided. In the embodiment of the Fig. 3 illustrates different geometries of sealing webs 400, which taper in an arrow-shaped or wedge-shaped manner in the direction of the bearing journal 111a and protrude into associated recesses 111.4 in order to define a labyrinth seal along the bearing journal 111a.

[0044] In addition to the sealing webs 400 projecting into recesses 111.4, the sealing bush 4 of the Fig. 3 also has at least one additional shortened radial sealing ridge 402 on its shaft section 40. This shortened radial sealing ridge 402 lies opposite a shoulder 111.4a of the bearing journal 111.4. At this shoulder 111.4a, the diameter of the bearing journal 111a is consequently increased, in particular compared to a recess 111.4 adjacent along the longitudinal axis L. Along the longitudinal axis L, the shortened radial sealing ridge 402 and the shoulder 111.4a are offset from one another by a step distance a, so that the edges of the shortened radial sealing ridge 402 and the shoulder 111.4a are not aligned with one another. A gap extending along the longitudinal axis L and over the different sealing webs 400 and 402 between the sealing bush 4 and the outer surface of the bearing journal 111a is thus twisted several times in opposite directions and to different degrees.The sealing effect can thus be further increased by means of the additionally provided shortened radial sealing web 402 and the shoulder 111.4a.

[0045] In the version of the Fig. 4, the sealing bushing 4 is designed without radially projecting sealing ridges on its shaft section 40 and is thus intended more as a bearing bushing. In this variant, the sealing effect to prevent leakage is achieved via a sealing disc 6, which, in addition to the bearing bushing 2 and the sealing bushing 4, is arranged at the radially outer and inner ends of the bearing opening O and between the bushings 2 and 2. This sealing disc 6 (or sealing ring) is received in a recess 111.4 of the bearing journal 111a in order to provide a type of labyrinth seal in this variant as well.

[0046] In order to take into account a thermally induced expansion of the sealing disc 6 during operation, a narrow gap g3 is provided between an inner circumferential surface of the sealing disc 6 and the outer circumferential surface of the bearing journal 111a in the region of the recess 111.4.

[0047] To enable the sealing disc 6 to be mounted on the bearing journal 111a, the sealing disc 6 is also longitudinally slotted. A single longitudinal slot 601 again has a non-linear profile, so that two circumferentially extending circumferential sections 60a and 60b of the sealing disc 6, which are separated from each other by the slot 601, axially overlap each other and / or engage with each other. For this purpose, the slot 601 can, for example, be designed according to the Fig. 4B a V-shaped, corresponding to the Fig. 4C a Z-shaped, corresponding to the Fig. 4D an Ω-shaped or according to the Fig. 4E (around the longitudinal axis L) have a helical course. The exemplary ones in the Fig. 4B, Fig. 4C, Fig. 4D and Fig. The courses of a slot 601 shown in Fig. 4E can of course also be provided for a slot 401 in a sealing bushing 4 (or in the sealing bushing 5) of the embodiment variants explained above.

[0048] The sealing disc 6 is designed in this case such that, under the thermal conditions occurring during operation of the engine T, the sealing disc 6 rests against the inner wall or the outer surface 100 of the bearing opening O via its outer surface, thus providing a seal. Due to its positioning on the recess 111.4 of the bearing journal 111a, an overlap with the sealing disc 6 is provided, viewed in the axial direction, which acts as a seal, in particular as a seal under all (transient) thermal conditions. In this context, the longitudinal slot 601 is designed accordingly to compensate for the thermal behavior while still providing additional sealing.

[0049] The Fig. 5A / 5D, 5B / 5E and 5C / 5F illustrate further design variants of a proposed vane assembly.

[0050] At the one with the Fig. 5A and Fig. In the embodiment illustrated in Figure 5D, a sealing bushing 5 with several rows of radially extending sealing ridges 500 is arranged between the bearing bushing 2 and a sealing bushing 4 designed as an additional bearing bushing without a radially extending sealing ridge. This sealing bushing 5 is formed, for example, in two parts, for example with two bushing halves, and is mounted on a recess 111.5 of the bearing journal 111a. The individual sealing ridges 500 extend radially inward relative to the longitudinal axis L.

[0051] In contrast, the version of the Fig. 5B and Fig. 5E, a sealing bushing 5 is arranged between bushings 2 and 4 in a recess 111.5 of the bearing journal 111a, with the multiple rows of sealing ridges 500 extending radially outward. A labyrinth seal is thus defined in the area between the inner circumferential surface 100 of the bearing opening O and the sealing ridges 500 of the sealing bushing 5.

[0052] In the version of the Fig. 5C and Fig. 5F is a sealing bush 4 comparable to the design variant of the Fig. 1A to 1C. The sealing bushing 4 comprises several rows of radially extending sealing webs 400 on a shaft section 40 extending from the bushing edge 41 into the bearing opening O along the longitudinal axis L. The sealing bushing 4 is in two parts.

[0053] The Fig. 6A and Fig. 6B show a further embodiment of a two-part sealing bushing 4, in which the circumferential sections 40a and 40b belonging to different bushing halves or parts are separated from each other by a Z-shaped longitudinal slot 401 and are adjacent to each other in the assembled state. Fig. 6A and Fig. 6B shows the sealing bushing 4 under two different thermal boundary conditions.

[0054] In a cold state according to the Fig. 6A, the overlapping circumferential sections 40a, 40b of the sealing bushing 4 abut one another, or at least almost abut one another, in the region of a central (second) slot section 401b. This central slot section 401b forms a transition between a first slot section 401a and a third slot section 401c, each of which runs substantially parallel to the longitudinal axis L.

[0055] At higher temperatures and thus higher thermal loads, the parts of the sealing bushing 4 and thus their peripheral sections 40a, 40b expand in the circumferential direction. This closes the slot sections 401a and 401c. In contrast, in the area of ​​the central, obliquely extending support section 401b, a (larger) gap forms between the adjacent parts of the sealing bushing 4. During operation of the engine T, the slot 401 is thus (sealingly) closed in the area of ​​its slot sections 401a and 401b. The multi-part sealing bushing 4 of the Fig. 6A and Fig. 6B (and analogously also the sealing elements 4, 5 and 6 explained above) can therefore be configured and designed such that the slot 401 on the sealing bushing 4 closes during operation of the engine T due to the thermal expansion that occurs.

[0056] Using the above-described design variants of guide vane assemblies, leakage flow along the bearing journal 111a through the bearing opening O in the casing 1 from the annular space RR to the outside is effectively prevented via at least one bush-shaped or disc-shaped sealing element 4, 5, 6. In order to ensure low-friction contact between the sealing element 4, 5 and / or 6, which is subject to high thermal stress during operation of the engine T, on the one hand, and the outer surface of the bearing journal 111a and / or the inner surface 100 of the bearing opening O, on the other hand, the respective sealing element 4, 5, 6 can be made, for example, from a lubricious plastic material, such as thermoplastics, polyamide, polyamideimides, polyimides, each with and without graphite infiltration and with and without PTFE content. Alternatively, the use of infiltrated graphite for the sealing elements with higher operating temperatures is also possible. List of reference symbols 1 housing 10 Lager process 100 Inner surface 10a Radial outer edge surface 10b Radial inner edge surface 11 low-pressure compressors 110 blade 111 Guide vane 111.4 Return 111.4a paragraph 111.5 Return 111a Bearing journal 111b tenon end 12 high-pressure compressors 12a - 12d Blade row 13 High-pressure turbine 13a - 13c Guide vane row 14 medium-pressure turbine 15 Low-pressure turbine 2 bearing bush / bearing disc 20 adhesive surface 3 Adjustment device 30 Adjustment ring 31 Adjustment lever 4 Sealing bushing (sealing element) 40 shaft section 400 Radial sealing bar 401 slot 401a, 401b,401c slot section 402 (shortened) radial sealing land 40a, 40b circumferential section 41 Bushing edge (bearing section) 5 Sealing bushing (sealing element) 500 Radial sealing bar 6 Sealing disc (sealing element) 601 slot 60a, 60b circumferential section A Outlet A step spacing B Bypass channel BK combustion chamber section D Rotary axis / spindle axis E Intake F Fan g1, g2, g3 gap I Interior L Longitudinal axis M Central axis / rotation axis O Warehouse opening R Entry direction RR annulus T gas turbine engine TT Turbine V Compressor

Claims

[1] Guide vane assembly for an engine (T), comprising at least one guide vane (111) of a guide vane row (13a-13c) and a housing (1) for the at least one guide vane row (13a-13c), wherein the at least one guide vane (111) is adjustably mounted on the housing (1) via a bearing pin (111a) which is rotatably mounted in a bearing opening (O) in the housing (1) and passes through this bearing opening (O) along a longitudinal axis (L), wherein a section (40) of a sealing element (4, 5, 6) is provided within the bearing opening (O), on which section at least one sealing web (400, 500) extending radially with respect to the longitudinal axis (L) is formed and / or which has a non-linear slot (401, 601) traversing the section (40) longitudinally, characterized by , that (a) the at least one radially extending sealing web (400, 500) extends into a recess (111.4, 111.5) of the bearing journal (111a) or (b) at least two sealing webs (400, 500) are formed on the section (40) provided within the bearing opening (O) and are arranged one after the other along the longitudinal axis (L), and the section formed with the at least two radially extending sealing webs (400, 500) is received in a recess (111.4, 111.5) of the bearing journal (111a), and the at least two sealing webs (400, 500) extend radially outwards in the direction of an inner circumferential surface (100) of the bearing opening (10). [2] Guide vane assembly according to claim 1, characterized by that the section (40) of the sealing element (4, 5, 6) provided within the bearing opening (O) forms a labyrinth seal to prevent leakage flow through the bearing opening (O) and along the bearing journal (111a). [3] Guide vane assembly according to claim 1 or 2, characterized bythat the at least one radially extending sealing web (400, 500) tapers at least in one web section in the direction of the bearing journal (111a). [4] Guide vane assembly according to one of the preceding claims, characterized by in that, in the case of a sealing web (400, 500) extending radially into a recess (111.4, 111.5) of the bearing journal (111a), the at least one sealing web (400, 500) has an end region which bears frictionally against an outer circumferential surface of the bearing journal (111a), which end region is intended to be scraped off at least partially by the adjustment of the bearing journal (111a) about the longitudinal axis (L) during operation of the engine (T). [5] Guide vane assembly according to one of the preceding claims, characterized byin that the sealing element (4), in addition to the section (40) formed with the at least one radially extending sealing web (400), has a bearing section (41) via which the sealing element (4) bears against an edge surface (10b) of the housing (1) which is located radially inward relative to a central axis (M) of the guide vane row (13a-13c) of the at least one guide vane (111) and which borders the bearing opening (10). [6] Guide vane assembly according to one of the preceding claims, characterized by that at least two sealing elements (4, 5, 6) are provided, each of which has a section (40) within the bearing opening (O), on which at least one sealing web (400, 500) extending radially with respect to the longitudinal axis (L) is formed and / or which has a non-linear slot (401, 601) traversing the section (40) longitudinally. [7] Guide vane assembly according to one of the preceding claims, characterized bythat the sealing element (4, 5, 6) is bush-shaped or disc-shaped. [8] Guide vane assembly according to one of the preceding claims, characterized by that the non-linear slot (401, 601) which longitudinally traverses the section (40) of the sealing element (4, 5, 6) provided within the bearing opening (O) has a discontinuous course. [9] Guide vane assembly according to one of the preceding claims, characterized by that the non-linear slot (401, 601) which longitudinally traverses the section (40) of the sealing element (4, 5, 6) provided within the bearing opening (O) has a helical, Z-, V- or Ω-shaped course. [10] Guide vane assembly according to one of the preceding claims, characterized by that the sealing element (4, 5) is formed in several parts and two parts of the sealing element (4, 5) adjoin one another along the slot (401). [11] Guide vane assembly for an engine (T), with at least one guide vane (111) of a guide vane row (13a-13c) and a housing (1) for the at least one guide vane row (13a-13c), wherein the at least one guide vane (111) is adjustably mounted on the housing (1) via a bearing pin (111a) which is rotatably mounted in a bearing opening (O) in the housing (1) and passes through this bearing opening (O) along a longitudinal axis (L), wherein a section of a sealing element (4, 6) is provided within the bearing opening (O), which has a non-linear slot (401, 601) extending longitudinally through the section, characterized by , that the sealing element has a sealing bushing (4) and a sealing disc (6), wherein the sealing disc (6) is received in a recess (111.4) of the bearing journal (111a), wherein a narrow gap (g3) for providing a labyrinth seal is provided between an outer circumferential surface of the bearing journal (111a) in the region of the recess (111.4) and an inner circumferential surface of the sealing disc (6), while an outer circumferential surface of the sealing disc (6) bears sealingly against an inner circumferential surface (100) of the bearing opening (O). [12] A gas turbine engine comprising a guide vane assembly according to any one of claims 1 to 11.

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