EP3176385B1 - Guide- blade rim housing for a turbomachine and turbomachine with guide- blade rim housing - Google Patents

Description

The invention relates to a vane ring housing for a turbomachine, a segment of a vane ring housing, a kit for a turbomachine and a turbomachine with a vane ring housing.

Flow machines (e.g. aircraft engines and stationary gas turbines) often have at least one row of guide vanes on the compressor side with a large number of guide vanes in order to set optimal operating conditions. The guide vanes preferably have a vane plate in each case in an area to be positioned radially on the inside and in an area to be positioned radially on the outside, which vanes can each have a pin on its side facing away from the blade airfoil. The guide vanes are to be fixed or fixed radially on the inside on an inner ring and radially on the outside on a guide vane ring housing; Unless otherwise stated, the designations "radial", "axial" and "direction of rotation" in this document always refer to a central geometric axis of the guide vane ring housing (in the direction of an intended main flow) on which a rotational axis of a rotor in the guide vane ring housing to position or is positioned. In the assembled state, the central geometric axis of the guide vane ring housing and a central axis of the inner ring therefore preferably match.

The guide vanes to be mounted or mounted between the inner ring and guide vane ring housing are advantageously mounted such that they can pivot about their longitudinal axis. For this purpose, the pins that are mounted on the guide vane ring housing (and which are then referred to as "adjustment pins") can interact with an adjustment device, via which pivoting can be effected.

The guide vane ring housing can be composed of several guide vane ring housing parts, each of which can have receptacles for vane disks. Such guide vane ring housing parts can include, for example, ring segments and/or axially separate parts.

The guide vane ring housing preferably has a plurality of receptacles extending in the radial direction, in each of which a corresponding vane plate of a guide vane is or can be inserted. Such a vane plate serves to stabilize or mount the guide vanes. The receptacle can be set up to also receive a pin arranged on the blade disk, possibly together with an associated bushing and/or a sliding disk for the blade disk.

The receptacles in the vane ring housing are separated from one another in the circumferential direction by respective partitions. Turbomachines with guide vane rings according to the prior art are in the documents WO 2015/079144 A1 , U.S. 2014/0140822 A1 and EP 1 760 272 A2 shown.

During manufacture of the vane ring housing and during operation of the vane ring, there is a risk that such a dividing wall will partially yield and in this way be pressed into an adjacent receptacle, which as a result no longer has its exact shape; this may prevent intended pickup of a paddle disc. The partition of the turbomachine can also be bent in the direction of an adjacent receptacle during operation and thus impair the pivotability of a guide vane inserted therein.

In order to reduce the risk of such a deformation of the mounts, conventional vane ring housings are therefore manufactured with a minimum wall thickness for the partition walls, which they must have at their thinnest point.

With a given inner circumference of the guide vane ring housing, the number of seats for vane plates (and thus the number of guide vanes that can be mounted) is determined by the given vane plate sizes and the minimum wall thickness to be observed. These parameters therefore have a limiting effect on the design of the turbomachine with a large number of pivotable guide vanes or large vane disks. However, such a design and/or a minimum size of the vane plates is often advantageous in terms of aerodynamics and/or structural mechanics.

The object of the present invention is to provide a technique that enables an aerodynamically and/or mechanically improved design of a row of guide vanes.

The object is achieved by a vane ring housing according to claim 1, by a segment of a vane ring housing according to claim 5, by a kit for a turbomachine according to claim 6 and a turbomachine according to claim 8. Advantageous embodiments are disclosed in the dependent claims, the description and the figures.

A guide vane ring housing according to the invention for a turbomachine has an inner housing surface which runs around a central (geometric) axis (preferably essentially along a cylinder or cone surface) and faces this axis; the central axis is preferably arranged in such a way that, in the assembled state, an axis of rotation of a rotor inserted into the guide vane ring housing coincides with the central axis.

A plurality of receptacles are arranged in the surface of the housing, each for a vane disk of a guide vane. Between at least two adjacent receptacles, the housing surface has a radial recess that connects the two receptacles (in the circumferential direction) to one another.

A segment of a guide vane ring housing according to the invention can be assembled with at least one other segment to form a guide vane ring housing according to the invention (according to one of the embodiments disclosed in this document). It comprises the at least two adjacent receptacles for blade disks, which are connected to one another by a radial recess. A segment according to the invention is preferably designed as a ring segment, for example as a half, third or quarter ring.

A kit according to the invention for a turbomachine comprises a guide vane ring housing according to one of the embodiments disclosed in this document and one or more guide vanes that are each inserted or are to be inserted in one of the receptacles of the guide vane ring housing.

A turbomachine according to the invention comprises a row of guide vanes, which has a plurality of guide vanes and a guide vane ring housing according to the invention has one of the embodiments disclosed in this document, in the recordings of which a guide vane plate of the guide vanes is inserted.

A vane ring housing according to the invention, a segment of a vane ring housing according to the invention, a kit according to the invention and a turbomachine according to the invention each advantageously enable an arrangement of guide vanes in which a distance between adjacent guide vane plates can be minimized and at the same time the risk of deformation of a receptacle can be avoided: especially when two adjacent Recordings have circular-cylindrical sections, they converge radially inward. In the area of the inner housing surface (facing the central axis), they are therefore at the smallest distance from one another. According to the present invention, no minimum distance needs to be maintained in this area in order to prevent a partition wall that is too thin from being unfavorably deformed in this area: According to the invention, in this narrowest area there is a recess in the housing surface between the receptacles, so that a partition wall , which could deform, is not present there.

In particular, a guide vane ring housing according to the invention enables the design with a large number of guide vanes or with large guide vane disks and thus an improvement in the efficiency and durability of a turbomachine.

The at least two receptacles preferably have the same dimensions, that is to say they have the same shape.

An embodiment variant is advantageous in which the at least two receptacles each have an essentially circular-cylindrical section (e.g. a circular-cylindrical bore) which runs radially in relation to the central axis of the guide vane ring housing. Such receptacles can accommodate correspondingly shaped guide vane plates with a circular-cylindrical section, which enables the guide vanes to be mounted and pivoted in a particularly secure and stable manner.

According to a preferred embodiment, the at least two receptacles are each set up to accommodate a guide vane plate which is attached to the blade airfoil Facing away (or opposite) side has a cylindrical adjusting pin. For this purpose, the at least two receptacles can each have two concentric cylindrical sections, one of which is located radially further outside (for receiving an adjusting pin) and is narrower than the one located radially further inside (for receiving the plate itself). The recess preferably extends in the radial direction (relative to the guide vane ring housing or a rotary shaft) up to a maximum (radial) depth of the radially inner cylindrical section of the receptacles. It therefore preferably only connects the radially inner sections (which have a larger diameter than the sections for accommodating the adjusting pins): In this way, as described above, a close arrangement of the guide vanes is made possible while maintaining high stability of the guide vanes used and low leakage .

According to an advantageous embodiment of the present invention, the receptacles in such a radially inner section have a radial depth (i.e. radial extent into the stator blade ring housing) which is preferably between 2 mm and 3 mm. Such dimensions make it possible to accommodate guide vane plates with the usual thickness (and possibly an additional sliding disk) without the surface of the guide vane plates to be arranged radially inward protruding from the inner surface of the housing (which would be disadvantageous in terms of flow).

According to an advantageous embodiment, the recess has a radial extent that is smaller than a radial depth of at least one of the receptacles or a radially inner cylindrical section of the receptacle. In particular, a partition wall is preferably formed between the at least two receptacles of a guide vane ring housing according to the invention, which partition wall extends radially between a bottom surface of at least one of the receptacles and the radial recess; the bottom surface is a surface that radially outwardly delimits at least part of the receptacle. In particular in one embodiment in which the receptacle has a radially outer section for receiving an adjusting pin and a radially inner section for receiving the vane plate itself, the bottom surface preferably forms a radial contact surface for the vane plate and an opening is arranged in the bottom surface through which the adjusting pin can be pushed.

Said dividing wall is therefore preferably located radially further outwards than the recess which connects the adjacent receptacles to one another. In this area, sections of the receptacles that may have a circular-cylindrical shape are further apart, so that there is no risk of the partition wall deforming. The dividing wall thus allows a secure and stable mounting of the guide vanes used there and, if necessary, a stable positioning of a sliding disk between the bottom surface and the vane plate and thus in an area in which a dividing wall thickness is not critical due to the radially outwardly spaced-apart receptacles.

Preferably, the partition has a base that is circumferentially inwardly curved (concave) on both sides; it can therefore accommodate a circular sliding disk with a precise fit and therefore with little leakage.

According to an advantageous embodiment, the dividing wall has a radial height of between 1 mm and 1.5 mm. A distance between a base of at least one of the receptacles and the radial recess is referred to as the radial height; if the at least two recordings have different radial depths, a bottom of the recording that has the smaller depth is to be selected.

Such a radial height reduces leakage between the at least two receptacles in a region that is not critical for the partition wall thickness and also enables a sliding disc that may be provided to be received between the receptacle base and a guide vane plate to be used.

An embodiment is advantageous in which the partition has a length in the axial direction of between 10 mm and 20 mm; In this way, an unfavorably small partition wall thickness on the side of a center of the recess (e.g. in a narrowest area between two receptacles) can be avoided.

At a point that is thinnest in the circumferential direction, the partition wall preferably has a thickness of between 0.3 mm and 0.5 mm. This can on the one hand a deformation of the Partition can be prevented when inserting the vanes or in use, on the other hand, such a thickness allows an advantageously narrow design of the vanes.

Sliding washers are preferably inserted into the receptacles between the guide vane ring housing and the guide vanes; a kit according to the invention or a turbomachine according to the invention can preferably include sliding disks of this type. You can bring about a reduction in friction when adjusting the vanes.

Preferred exemplary embodiments of the invention are explained in more detail below with reference to drawings. It goes without saying that individual elements and components can also be combined differently than shown. Reference symbols for elements that correspond to one another are used throughout the figures and may not be described anew for each figure.

They show schematically:

Figure 1:

a portion of a conventional vane ring housing in a perspective view;

Figure 2:

a portion of an exemplary nozzle ring case according to the invention;

Figure 3:

a section of an exemplary guide vane ring housing according to the invention with a guide vane to be used in an exploded view.

In the figure 1 a segment of a conventional guide vane ring housing 10 is shown, which in the present example is essentially semi-annular. Together with another similarly designed segment (not shown), the guide vane ring housing 10 has an (abstract) central geometric axis A, which coincides with the axis of rotation of a rotor (not shown in the figure) when the turbomachine is installed. The segment shown has a mounting edge 19 with holes for screw connections for assembly or assembly with other parts of the guide vane ring housing.

That in the figure 1 The segment of a guide vane ring housing 10 shown has on its inner housing surface 11 three ring-like regions arranged axially one behind the other (one below the other in the illustration), each of which includes a plurality of receptacles 12 for vane disks of guide vanes. The areas have different radii, so that the inner housing surface tapers in stages in the intended main flow direction R (from bottom to top in the figure). Between the sections with the receptacles 12 there are areas of the housing surface 11 which are arranged on a cylindrical surface.

In their center, the receptacles 12 each have a pin receptacle 17 which is designed to receive an adjusting pin on a vane plate. The adjusting pins and thus the associated guide vanes can preferably be pivoted via an adjusting mechanism (not shown) lying radially on the outside.

In the figure 1 the recordings of the central area blade plate 21a are equipped with guide vanes 20. The guide vanes 20 each have vane disks 21b on the side opposite the vane disks 21a, which are designed to be inserted into receptacles in an inner ring (not shown).

How from the figure 1 As can be seen, the receptacles 12 are separated from one another by partitions in a conventional manner. These partitions are very thin, particularly in the narrowest area (uppermost in the figure), so that deformations can occur, as described above.

In the figure 2 in contrast, a section of a housing surface 11 of a guide vane ring housing according to the invention is outlined; the case surface faces a central axis (not shown) of the vane case.

In the housing surface 11, receptacles 12' are arranged, into which radially outer vane disks of suitable guide vanes are to be inserted. Opposite the openings of the receptacles 12' in the housing surface 11, the receptacles each have an annular bottom surface 14, in the center of which is a pin receptacle 17 for a Adjusting pin of the respective vane is arranged. In the example shown, the receptacles 12 ′ each have the same shape and, in particular, have a circular-cylindrical basic shape, from which (concentrically) the (likewise circular-cylindrical) pin receptacle 17 is arranged.

The housing surface 11 has between the in the figure 2 shown adjacent recordings 12 'a radial recess 16 which connects the adjacent recordings together. The recesses each have a radial depth t, which is preferably in a range from 1 mm to 1.5 mm.

A partition wall 15 is formed between the adjacent receptacles 12', which partition wall 15 extends between the bottom 14 of the receptacles and the recess 16 (or radially in relation to a central axis of the guide vane ring housing). The partition wall 15 has a radial height h, which is preferably between 1 mm and 1.5 mm. Such a height enables an advantageous centering of the blade disks or sliding discs to be used and reduces leakage in this area.

In the axial direction (relative to a central axis of the vane ring housing), the partition wall has a length 1; this is preferably between 10 mm and 20 mm. In the example shown, the partition wall 15 has a base that is curved inward on both sides in the circumferential direction. In the circumferential direction, the partition wall 15 has a thickness d ₁ at its thickest point (at its ends) and a thickness d ₂ at its thinnest point; preferably d _{2 is} in a range from 0.3 mm to 0.5 mm; thus the risk of deformation of the partition wall can be minimized. The thickness d ₁ (at the thickest point of the dividing wall 15) results from d ₂ , the length of the dividing wall and the radius of the receptacles 12'. Preferably, d _{1 is} in a range between 2.5 mm and 3 mm.

In figure 3 a section of a guide vane ring casing 10' according to the invention is shown. The vane ring housing 10' has a housing surface 11 with receptacles 12', adjacent ones of which are connected to one another by a recess 16 in the housing surface 11. In a bottom surface 14 of the receptacles, they each have a pin receptacle 17 into which a bushing 31 for the adjusting pin 23 of a guide vane 20 is inserted.

In an exploded view is in the figure 3 Illustrates by way of example how such a guide vane 20 with a guide vane plate 21a and the adjustment pin 23 extending therefrom is to be inserted into the guide vane ring housing; A sliding disk 30 is inserted between the blade plate 21a and the bottom surface of the receptacle 12', which is designed as a ring through which the adjusting pin is pushed.

A guide vane ring housing 10′ according to the invention for a turbomachine has a housing surface 11 running around a central axis A and facing the axis, in which a plurality of receptacles 12′ each for a vane disk 21a of a guide vane 20 are arranged. A radial recess 16 is arranged in the housing surface 11 between at least two adjacent receptacles 12' and connects the two receptacles to one another.

A segment according to the invention of a guide vane ring housing according to the invention (according to one of the embodiments disclosed in this document) comprises the at least two adjacent receptacles 12 ′ connected to one another by a radial recess 16 .

A kit according to the invention for a turbomachine comprises a guide vane ring housing 10' according to the invention (according to one of the embodiments disclosed in this document) and one or more guide vanes 20, each of which is to be inserted into one of the receptacles 12' and/or at least some of which are inserted .

A turbomachine according to the invention comprises a plurality of guide vanes 20 and a guide vane ring housing 10' according to the invention (according to one of the embodiments disclosed in this document), in whose receptacles 12' a guide vane disk 21a of the guide vanes is inserted.

Reference sign

10, 10'

Vane Ring Casing

11

housing surface

12, 12'

admission

14

floor space

15

partition wall

16

recess

17

trunnion mount

19

mounting edge

20

vane

21a, 21b

scoop disc

23

adjustment pivot

30

sliding disc

31

Rifle

A

central axis

R

intended main flow direction

d1

Thickness of the partition at its thickest point

d2

Thickness of the partition at its thinnest point

H

radial height of the partition

1

Partition wall length (in axial direction)

t

radial depth of recess

Claims (9)

1. Guide vane ring housing (10') for a turbomachine, which housing comprises a housing surface (11) that extends around a central axis (A) and faces the axis, a plurality of receptacles (12') each intended for a vane disk (21a) of a guide vane (20) being arranged in the housing surface,
   characterized in that
   the housing surface (11) has a radial recess (16) between at least two adjacent receptacles (12') which interconnects the two receptacles.
2. Guide vane ring housing according to claim 1, wherein the receptacles (12') each comprise a substantially cylindrical portion which extends radially into the housing.
3. Guide vane ring housing according to either claim 1 or claim 2, wherein a dividing wall (15) is formed between the at least two receptacles, which wall extends radially between a base (14) of at least one of the receptacles and the radial recess (16).
4. Guide vane ring housing according to claim 3, wherein the dividing wall has a radial height (h) of between 1 mm and 1.5 mm

   and/or wherein the dividing wall has a length (1) of between 10 mm and 20 mm in the axial direction

   and/orwherein the dividing wall has a thickness (d2) of between 0.3 mm and 0.5 mm in the circumferential direction at a thinnest point.
5. Segment of a guide vane ring housing according to any of claims 1 to 4, wherein the segment comprises the at least two adjacent receptacles (12') interconnected by a radial recess (16).
6. Assembly for a turbomachine, which assembly comprises a guide vane ring housing (10') according to any of the preceding claims and one or more guide vanes (20), each of which is intended to be inserted or is inserted into one of the receptacles (12').
7. Assembly according to claim 6, which also comprises a plurality of sliding washers (30), each of which is to be inserted or is inserted into the receptacles (12') between the guide vane ring housing and each of the guide vanes (20).
8. Turbomachine having a row of guide vanes which comprises a plurality of guide vanes (20) and a guide vane ring housing (10') according to any of claims 1 to 4, into each receptacle (12') of which a guide vane disk (21a) of the guide vanes is inserted.
9. Turbomachine according to claim 8, which also comprises a plurality of sliding washers (30) which are each inserted into the receptacles between the guide vane ring housing (10') and each of the guide vanes (20).

Images