Ellipsoidal inner central blade storage space

Abstract

An inner ring according to the invention or an inner ring segment according to the invention for an adjustable guide vane assembly comprises a plurality of uptakes, each for the bearing of an adjustable guide vane. The uptakes here each form an essentially ellipsoidally shaped uptake space for a guide vane head of the respective guide vane. A guide vane according to the invention for an adjustable guide vane assembly has a blade body and a guide vane head. The guide vane head is essentially ellipsoidal in shape and is equipped to be accommodated pivotably in an uptake of an inner ring or inner ring segment of the guide vane assembly.

Claims

1. An inner ring for an adjustable guide vane assembly, comprising: an inner ring having a plurality of uptakes, each for the bearing of an adjustable guide vane, wherein the uptakes each create an essentially ellipsoidally shaped uptake space for a guide vane head of the respective guide vane.

2. The inner ring according to claim 1, wherein the essentially ellipsoidally shaped uptake space of the uptakes is configured and arranged, in each case, substantially rotationally symmetric with respect to a radially directed axis.

3. The inner ring according to claim 1, wherein the inner ring is divided in the axial direction and/or in the peripheral direction.

4. The inner ring according to claim 1, wherein at least one part of a contact surface of the inner ring, which is provided in the uptakes for contact with a guide vane head region of a guide vane, has a coating for reducing frictional losses and/or wear.

5. The inner ring according to claim 1, wherein an inner ring segment for the inner ring contains at least one of the uptakes, which forms an essentially ellipsoidally shaped uptake space for a guide vane head of a guide vane.

6. The inner ring according to claim 1, wherein an inner ring and a plurality of adjustable guide vanes are configured into a guide vane assembly.

7. The inner ring according to claim 6, wherein the guide vane assembly is configured and arranged in a turbomachine having at least one compressor stage and/or turbine stage.

8. A guide vane for an adjustable guide vane assembly, comprising: a vane body and a guide vane head, wherein the guide vane head is pivotably positioned in an uptake of an inner ring or inner ring segment of the guide vane assembly, and wherein the guide vane head is substantially ellipsoidal in shape.

9. The guide vane according to claim 8, wherein the ellipsoidally shaped guide vane head is configured and arranged rotationally symmetric with respect to a pivot axis of the guide vane.

10. The guide vane according to claim 8, wherein at least a part of a surface of the guide vane head has a coating for reducing frictional losses and/or wear.

11. The guide vane of claim 8 having an inner ring and a plurality of adjustable guide vanes.

Description

BRIEF DESCRIPTION OF THE DRAWING FIGURES

(1) Preferred exemplary embodiments of the invention will be described below in detail on the basis of drawings. It is understood that individual elements and components can also be combined in a different way than illustrated.

(2) Shown schematically are:

(3) FIG. 1: a section of an exemplary guide vane assembly according to the invention in a meridional section;

(4) FIG. 2: an inner ring segment in accordance with an exemplary embodiment of the present invention in a meridional section;

(5) FIG. 3a: a section of a guide vane in accordance with an embodiment of the present invention;

(6) FIG. 3b: a section of a guide vane in accordance with another embodiment of the present invention; and

(7) FIG. 3c: a section of a guide vane in accordance with another embodiment of the present invention.

DESCRIPTION OF THE INVENTION

(8) Illustrated in FIG. 1 is a section of an exemplary guide vane assembly 1 according to the invention in a meridional section along the central X axis of the guide vane assembly (or of its inner ring 10). In this case, the meridional section runs additionally along the provided pivot axis S of a guide vane 20 of the guide vane assembly 1.

(9) The illustrated guide vane 20 according to the invention comprises a vane body 21 and a guide vane head 22, which is an end of the guide vane 20 that is positioned radially inward (in relation to the central X axis of the guide vane assembly). The guide vane head 22 is ellipsoidal in shape and thus has a region 22a that coincides with the surface of an ellipsoid.

(10) At a side facing away from the vane body, the guide vane head 22 projects over a leading edge 25 of the guide vane.

(11) By means of an adjustable pin 24, which is equipped to be inserted into a housing (having an adjusting device not shown in FIG. 1), the guide vane 20 can pivot around a pivot axis S directed radially relative to the central X axis.

(12) The illustrated inner ring 10 according to the invention (which can be composed of two or more inner ring segments) has a plurality of uptakes for respective guide vanes, of which only the uptake 11 can be seen in the sectional illustration. The uptake 11 hereby forms, in a radially inner section, an ellipsoidally shaped uptake space 12 for the guide vane head 22. In the example shown, besides the ellipsoidally shaped guide vane head 22, also a transition region 23 of the guide vane is accommodated in the uptake 11 of the inner ring 10.

(13) An intermediate space 30 between the guide vane head and a wall of the uptake (which may also be referred to as a penny gap) can be designed as optimally small on account of the bearing arrangement in accordance with the invention of the guide vane 20 together with its essentially ellipsoidally shaped guide vane head 22 in an uptake 11 with the correspondingly shaped uptake space 12. This bearing arrangement is, in addition, compact, robust, and low-wear.

(14) Facing the central X axis, the inner ring inner ring 10 comprises a sealing element 13, which, in the example shown, is designed as a honeycomb seal and is monolithically molded on the inner ring 10.

(15) Shown in FIG. 2 is an inner ring 10 segment according to the invention in a meridional section through an uptake 11 and along a central X axis of the inner ring segment 10 (or of an inner ring that forms the inner ring segment together with at least one other inner ring segment). The sectional plane in this case comprises the provided pivot axis S of a guide vane that is to be inserted into the uptake 11 (not illustrated).

(16) The uptake 11 forms an essentially ellipsoidally shaped uptake space 12 for a guide vane head of the respective guide vane; the uptake space 12 is bounded by a part of the surface of an (abstract) ellipsoid E, along which a wall 14 of the uptake runs. The wall 14 comprises, in particular, a bottom surface 15 of the uptake, which lies radially opposite to an opening 16 of the uptake (which faces a guide vane to be inserted). Besides the essentially ellipsoidal uptake space 12, the uptake 11 comprises another region 17.

(17) The ellipsoid E has half-axes a and b, which are indicated in the figure, as well as another half-axis that is directed perpendicularly to the plane of the illustration. Preferably, this additional half-axis has the same length as the half-axis a, so that the ellipsoid E therefore is a rotational ellipsoid, the rotational axis of symmetry of which coincides with the pivot axis S.

(18) Upstream of a provided main flow direction R, the wall 14 that bounds the essentially ellipsoidally shaped uptake space 12 adjoins the radially outer inner ring surface 18. The wall 14 in this case is inclined with respect to the inner ring surface 18 by an outer angle that is less than 270. In this way, it can be prevented that a renewed inflow of the leakage mass flow occurs perpendicularly to the outer inner ring surface, which would result in a disruption of the main gas flow and thus additional flow losses.

(19) The uptake 11 of the inner ring segment 10 further comprises two grooves 19a, 19b, which each run in a section in a plane perpendicular to the provided pivot axis S (not visible in the sectional illustration) and are each equipped to accommodate a securing projection at the guide vane head of a guide vane (not illustrated) that is to be inserted. For insertion, the two grooves each comprise a section leading to the opening 16.

(20) FIGS. 3a, 3b, and 3c each show a section of an adjustable guide vane 20, 20, and 20 of different embodiments according to the invention in a sectional plane that comprises the provided pivot axis S. The guide vanes here each have a vane body 21, 21, or 21 and an essentially ellipsoidally shaped guide vane head 22, 22, or 22. In these examples, the associated ellipsoid is a half-ellipsoid in each case.

(21) Indicated in the figures are the half-axes a.sub.i, b.sub.i (i=1, 2, 3) of the ellipsoids, which lie in the sectional plane and in accordance with which the guide vane heads are each formed. The half-axes b.sub.i (i=1, 2, 3) are each directed in the direction of the provided pivot axis S. A third (not visible) half-axis is directed orthogonally to the sectional plane. Its length preferably matches, in each case, the length of the corresponding half-axis a.sub.i, so that, in each case, the ellipsoids are then rotationally symmetric with respect to the pivot axis S.

(22) In the exemplary embodiment shown in FIG. 3a, the half-axis b.sub.1 is longer than the half-axis a.sub.1; the guide vane head is therefore equipped to be inserted into a relatively deep uptake of an inner ring (segment). In this way, the bearing arrangement is especially robust.

(23) For the guide vane 20 shown in FIG. 3b, in contrast, the half-axis b.sub.2 is shorter than the half-axis a.sub.2. This permits a bearing arrangement in an inner ring that is especially thin (in the radial direction) and is especially easy to intermesh.

(24) In the example shown, the guide vane head 22 has two (optionally present) securing elements 24a, 24b, which, in the present case, are formed as projections and project from the guide vane head. The securing elements 24a, 24b are each equipped for engaging in a suitable groove in an uptake of an inner ring and thus to secure the guide vane similarly to a bayonet connection at the inner ring.

(25) The guide vane 20, which is illustrated in FIG. 3c, has a guide vane head, for which the lengths of the half-axes a.sub.3 and b.sub.3 match. As long as the third axis (not visible) also has this length, the guide vane head is therefore formed as a half-sphere.

(26) An inner ring 10 according to the invention or an inner ring segment 10 according to the invention for an adjustable guide vane assembly 1 comprises a plurality of uptakes 11, 11, each for bearing an adjustable guide vane 20, 20, 20, 20. The uptakes here each form an essentially ellipsoidally shaped uptake space 12 for a guide vane head 22, 22, 22, 22 of the respective guide vane.

(27) A guide vane 20, 20, 20, 20 according to the invention for an adjustable guide vane assembly 1 has a vane body 21, 21, 21, 21 and a guide vane head 22, 22, 22, 22. The guide vane head is essentially ellipsoidal in shape and is equipped to be pivotably accommodated in an uptake 11, 11 of an inner ring 10 or inner ring segment 10 of the guide vane assembly 1.