Flow channel for a turbomachine

Abstract

The present invention relates to a method for designing a flow channel for a turbomachine, in particular a gas turbine that comprises a guide vane cascade having a plurality of guide vanes, which are distributed in the peripheral direction, and flow passages, each of which is bounded by two successive guide vanes, and a support rib arrangement having at least one support rib, wherein a design of one of the flow passages is adapted to this support rib, that it is situated downstream of, in order to reduce a pressure loss and/or a vibrational stimulation.

Claims

1. A method for designing a flow channel for a turbomachine that includes a guide vane cascade having a plurality of guide vanes, which are distributed in the peripheral direction, and flow passages, each of which is bounded by two successive guide vanes, and a support rib arrangement having at least one support rib, wherein a downstream edge of the at least one support rib is axially spaced apart from an upstream edge of the guide vanes, wherein a layout of one of the flow passages is changed in shape relative to one of the other adjacent flow passages by a change in shape of the guide vanes bounding said changed flow passage, which is situated downstream of the at least one support rib, to reduce a pressure loss and/or a vibrational stimulation.

2. The method according to claim 1, wherein, for at least the majority of all successive support ribs of the support rib arrangement in the peripheral direction, in each case, a layout of a flow passage of the guide vane cascade that is situated downstream of this support rib is adapted to this support rib in order to reduce a pressure loss and/or a vibrational stimulation.

3. The method according to claim 1, wherein the adaptation of the layout of at least one of these flow passages to the support rib that it is situated downstream of comprises a positioning of this flow passage in the peripheral direction in relation to this support rib in such a way that a trailing segment and/or a tangent at a point of a downstream end region of a camber line of the support rib intersect or intersects an inlet cross section of the flow passage in a middle region.

4. The method according to claim 1, wherein the adaptation of the layout of at least one of these flow passages to the support rib that it is situated downstream of comprises a change in a size of this flow passage when compared to at least one other of the flow passages.

5. The method according to claim 4, wherein the change in the size comprises an enlargement in a channel width in the peripheral direction, and the change in the shape of the one flow passage when compared to the at least one other flow passage comprises a change in a flow-passage-side pressure side of one of the two guide vanes, a flow-passage-side suction side of one of the two guide vanes that bound the one flow passage, in a stagger angle, or in a profile of at least one of these two guide vanes when compared to the other flow passage when compared to the guide vane or guide vanes bounding it.

6. The method according to claim 1, wherein the guide vane cascade is an inlet guide vane cascade of a turbine of a gas turbine, and the support rib arrangement is arranged in a mid turbine frame for the connection of two turbines of a gas turbine.

7. The method according to claim 1, wherein for at least the majority of all successive support ribs of the support rib arrangement in the peripheral direction, in each case, a flow passage, which is situated downstream of this support rib, and is adjacent, is positioned in relation to this support rib in the peripheral direction in such a way that a trailing tangent at a point of a downstream end region of a camber line of the support rib intersect or intersects an inlet cross section of the flow passage in a middle region, and a size of this flow passage is different from at least one other of the flow passages.

8. The method according to claim 1, wherein the at least one flow channel is configured and arranged in a gas turbine.

Description

BRIEF DESCRIPTION OF THE DRAWING FIGURES

(1) Additional advantageous enhancements of the present invention ensue from the dependent claims and the following description of preferred embodiments. Shown for this purpose, in part schematically, are:

(2) FIG. 1 is a part of a flow channel of a turbomachine in accordance with an embodiment of the present invention; and

(3) FIG. 2 is a one part of FIG. 1.

DESCRIPTION OF THE INVENTION

(4) FIG. 1 shows a part of a flow channel 1 of a turbomachine in accordance with an embodiment of the present invention or a design of the flow channel 1 according to a method in accordance with an embodiment of the present invention.

(5) The flow channel 1 has a guide vane cascade with a plurality of guide vanes, which are distributed in the peripheral direction, and flow passages, each of which is bounded by two successive guide vanes, of which, by way of example in FIG. 1, guide vanes 20-24 and flow passages 50-54 bounded (in part) by them are illustrated.

(6) The flow channel 1 further has a support rib arrangement with a plurality of support ribs, which are distributed in the peripheral direction and of which, by way of example in FIG. 1, a support rib 10, for which the flow passage 51 is adjacent downstream, and a support rib 100, for which the flow passage 54 is adjacent downstream, are illustrated.

(7) In the illustrated embodiment of FIG. 1, the support ribs 10, 100 run parallel to the axial direction; that is, they are not arranged or oriented at an inclination to the axial direction. In another embodiment, which is not illustrated, the support ribs 10 and/or 100 are inclined to the axial direction or oriented when compared to the axial direction at an angle of, for example, between 5° and 10°, such as, for instance, 5°, 6°, 7°, 8°, 9°, or 10°.

(8) A layout of these adjacent flow passages 51, 54 downstream of a support rib will be or is adapted in each case to the adjacent support rib 10 or 100 upstream thereof in order to reduce a pressure loss and/or a vibrational stimulation.

(9) For this purpose, the flow passage 51 is or will be positioned in the peripheral direction (vertical in FIG. 1) in relation to the support rib 10 in such a way that a trailing segment 12 (see FIG. 1) or a tangent 14 at a point of a downstream end region of a camber line 13 of the support rib 10 intersects an inlet cross section E of the flow passage 51 in a middle region, as illustrated in FIG. 2. In the same way, the flow passage 54 also is or will be positioned in the peripheral direction in relation to the support rib 100 in such a way that a trailing segment or a tangent at a point of a downstream end region of a camber line of the support rib 100 intersects an inlet cross section of the flow passage 54 in a middle region (not illustrated).

(10) Additionally, a channel width B in the peripheral direction (see FIG. 2) of the flow passage 51 is or will be enlarged when compared to the flow passages 50, 52, and 53.

(11) Additionally, a flow-passage-side pressure side 41 of the guide vane 21, which bounds the flow passage 51, is or will be altered or adapted, in particular, when compared to the flow-passage-side pressure sides 40 and 43 of the guide vanes 20 and 23, respectively, which bound the flow passage 50 or 53, respectively.

(12) Additionally, a flow-passage-side suction side 32 of the guide vane 22, which bounds the flow passage 51, is or will be altered or changed, in particular, when compared to the flow-passage-side suction sides 30 and 33 of the guide vanes 20 or 23, respectively, which bound the flow passage 50 or 53, respectively.

(13) Additionally, the stagger angles 1351, 1352 of the guide vanes 21, 22, which bound the flow passage 51, are or will be altered or adapted, in particular when compared to the stagger angle 1350 of the guide vane 20, which bounds the flow passage 50, as illustrated in FIG. 2.

(14) The same applies analogously to the flow passage 54 or the guide vanes bounding it, of which, in FIG. 1, only the guide vane 24 is shown.

(15) A rotating blade cascade 70 of a turbine or of a compressor is arranged downstream behind the guide vane cascade comprising the guide vanes 20-24. In the case of a turbine, a rotating blade cascade 60 of another turbine is arranged upstream in front of the support rib arrangement comprising the support ribs 10, 100. In the case of a compressor, a compressor guide vane cascade 60 is arranged upstream in front of the support rib arrangement comprising the support ribs 10, 100.

(16) Even though, in the preceding description, exemplary embodiments were explained, it is noted that a large number of modifications are possible. Moreover, it is noted that the exemplary embodiments are only examples, which in no way limit the scope of protection, the applications, and the structure. Instead, the preceding description affords the person skilled in the art a guideline for implementing at least one exemplary embodiment, with it being possible to carry out diverse changes, in particular in regard to the function and arrangement of the described component parts, without departing from the scope of protection as ensues from the claims and the combinations of features equivalent thereto.

(17) It would be appreciated by those skilled in the art that various changes and modifications can be made to the illustrated embodiments without departing from the spirit of the present invention. All such modifications and changes are intended to be covered by the appended claims.