Airfoil for a turbomachine

Abstract

The invention relates to an airfoil as well as to a method for producing an airfoil for a turbomachine, comprising a leading edge and a trailing edge joined to each other by a suction side and a pressure side and which, in at least one region, extends in a curved manner from an airfoil root to an airfoil tip, wherein the airfoil tip has a squealer tip, which is arranged at the airfoil tip.

Claims

1. An airfoil for a turbomachine, comprising: a leading edge and a trailing edge joined to each other by a suction side and a pressure side and which, in a least one region, extends in a curved manner from an airfoil root to an airfoil tip, wherein the airfoil tip has a squealer tip, which is arranged along a centroid curve at the airfoil tip, wherein the centroid curve passes through the centroidal axes of the airfoil.

2. The airfoil according to claim 1, wherein the squealer tip is arranged on both sides of the centroid curve.

3. The airfoil according to claim 1, wherein the squealer tip is arranged at least substantially symmetrically around the centroid curve.

4. The airfoil according to claim 1, wherein the squealer tip is configured and arranged to be continuous.

5. The airfoil according to claim 1, wherein a cross section of the squealer tip is smaller than a cross section of the airfoil tip.

6. An airfoil arrangement for a turbomachine, wherein the airfoil arrangement includes at least one airfoil according to claim 1.

7. A compressor for a turbomachine, wherein the compressor includes at least one airfoil arrangement according to claim 6.

8. A turbomachine, comprising at least one airfoil arrangement according to claim 6.

9. A compressor for a turbomachine, wherein the compressor includes at least one airfoil according to claim 1.

10. A turbomachine, comprising a compressor according to claim 9.

11. A turbomachine, comprising at least one airfoil according to claim 1.

12. A method for producing an airfoil for a turbomachine, comprising the following steps: a) determination of the centroidal axes of the airfoil depending on a blade geometry; b) determination of a centroid curve at an airfoil tip depending on the centroidal axes; c) determination of an arrangement of a squealer tip depending on the determined centroid curve; and d) production of the airfoil with a squealer tip in accordance with the arrangement determined in the step c).

Description

BRIEF DESCRIPTION OF THE DRAWINGS FIGURES

(1) Further features, advantages, and possible applications of the invention ensue from the following description in connection with the figures. Herein:

(2) FIG. 1 shows a schematic illustration of an exemplary airfoil according to the invention for a turbomachine;

(3) FIG. 2 shows a schematic illustration of a profile of an exemplary airfoil according to the invention for a turbomachine;

(4) FIGS. 3a to 3c show schematic illustrations of three airfoil cross sections of an exemplary airfoil according to the invention; and

(5) FIG. 4 shows a schematic diagram of a flow chart of an exemplary method for the production of an airfoil for a turbomachine.

DESCRIPTION OF THE INVENTION

(6) FIG. 1 shows an exemplary embodiment of an airfoil 10 for a turbomachine in a schematic illustration. The airfoil has a leading edge 11 and a trailing edge 12, which are joined to each other by a suction side 13 and a pressure side 14. The airfoil 10 hereby extends, in at least one region, in a curved manner from an airfoil root, which is not illustrated, to an airfoil tip 21. Such a curvature is indicated schematically by a change in the geometric profile 15.

(7) The airfoil tip 21 has an essentially continuously designed squealer tip 22, which is arranged along a centroid curve at the airfoil tip 21, with the centroid curve extending through the centroidal axes of the airfoil 10 (see FIG. 2). The squealer tip 22 hereby has a cross section, which, in particular, is orthogonal to the profile centerline, and which is smaller than such a cross section of the airfoil tip 21.

(8) FIG. 2 shows a schematic illustration of the airfoil tip 21 of the airfoil 10 from FIG. 1. The airfoil 10 extends between an inflow-side leading edge 11 and a trailing edge 12. The airfoil 10 has a suction side 13 and an opposite-lying pressure side 14.

(9) At each point, a profile centerline 16 has the same distance with respect to the suction side 13 and the pressure side 14 of the profile of the airfoil 10. A centroid curve K of the airfoil 10 extends at the airfoil tip 21 through centroidal axes of cross-sectional surfaces Q of the airfoil 10 that are perpendicular to the profile centerline 16.

(10) FIGS. 3a to 3c each show a schematic illustration of three airfoil cross sections of the exemplary curved airfoil 10 from FIG. 2. At its airfoil tip 21, the airfoil 10 has the squealer tip 22 with a suction-side flank 23 and a pressure-side flank 24.

(11) FIG. 3a shows a schematic illustration of the exemplary section A-A from FIG. 2 at a first centroidal axis S.sub.A in a first region of the airfoil 10. It can be seen in FIG. 3a that the squealer tip 22 has a height H starting from, in particular, an unchanged airfoil cross section and extending to the front end of the squealer tip 22. Furthermore, the squealer tip 22 has a width B, which is delimited by the suction-side flank 23 and the pressure-side flank 24 and is arranged, in particular, in an end region of the squealer tip 22, in which the suction-side flank 23 and the pressure-side flank 24 are designed to be at least essentially parallel to each other.

(12) The squealer tip 22 is arranged on both sides of the centroidal axis S.sub.A or of the centroid curve K, with a suction-side tapering 33 being arranged at the airfoil tip 21 of the airfoil 10 in order to form the suction-side flank 23 of the squealer tip 22. The pressure-side wall 14 of the airfoil 10 forms the pressure-side flank 24 of the squealer tip 22. The squealer tip can be designed in such a way, in particular, in a region facing the leading edge 11 and/or in a region spaced apart from an inflection point of the centroid curve K.

(13) FIG. 3b shows a schematic illustration of the exemplary section B-B from FIG. 2 at a second centroidal axis S.sub.B in a second region of the airfoil 10. The squealer tip 22 is hereby arranged essentially symmetrically around the second centroidal axis S.sub.B or around the centroid curve K. The airfoil tip 21 has a tapering 33, 34 on both the suction side and the pressure side, as a result of which the flanks 23, 24 of the squealer tip 22 are arranged displaced inward in relation to an airfoil cross section.

(14) FIG. 3c shows, a schematic illustration of the exemplary section C-C from FIG. 2 at a third centroidal axis Sc in a third region of the airfoil 10. The squealer tip 22 is still arranged on both sides of the centroidal axis Sc or of the centroid curve K, with a pressure-side tapering 34 being arranged at the airfoil tip 21 of the airfoil 10 in order to form the pressure-side flank 24 of the squealer tip 22. The suction-side wall 13 of the airfoil 10 forms the suction-side flank 23 of the squealer tip 22. The squealer tip 22 can be designed in this way, in particular, in a region facing the trailing edge 12 and/or in a region spaced apart from an inflection point of the centroid curve K.

(15) FIG. 4 shows a schematic illustration of a flow chart of an exemplary method 100 for designing or producing an airfoil 10 for a turbomachine.

(16) In a first step 101, centroidal axes S of the airfoil 10 are determined starting from a blade geometry. In a step 102, depending on the centroidal axes S, a centroid curve K is determined at the airfoil tip 21. In a further step 103, an arrangement of a squealer tip 22 is determined depending on the determined centroid curve K, and, in a step 104, the airfoil 10 with a squealer tip 22 is produced in accordance with the arrangement determined in step 103.