Turbomachine blade

Abstract

A blade (1) for a turbomachine, including an impact chamber (2), a single impulse body (3) being situated in the impact chamber, a clearance (S1+S2) between the impulse body and the impact chamber being at least 10 μm and/or at most 1.5 mm in at least one direction.

Claims

1. A blade for a turbomachine, comprising: an impact chamber; and a single impulse body movably situated in the impact chamber, a clearance between the impulse body and the impact chamber in all directions being at least 0.1 mm and at most 1.5 mm and wherein a mass of the impulse body is at least 10 mg and at most 1.5 g.

2. The blade as recited in claim 1 wherein the impulse body is provided with a spherical or disk shaped design.

3. The blade as recited in claim 1 wherein the impulse body is made from a nickel or cobalt alloy or a ceramic.

4. The blade as recited in claim 1 wherein the impact chamber has at least one pair of opposite, inner walls, each wall defining a preferred impact direction.

5. The blade as recited in claim 4 wherein the opposing inner walls are parallel.

6. The blade as recited in claim 1 wherein the impact chamber is situated in an outer shroud or a blade root of the blade.

7. The blade as recited in claim 1 wherein the impact chamber is situated in an outer shroud, the outer shroud vane extending radially.

8. The blade as recited in claim 1 wherein the impact chamber is closed by a cover.

9. The blade as recited in claim 8 wherein the cover is flush with an outer contour of the blade.

10. The blade as recited in claim 1 wherein the impact chamber, together with the blade, is formed in the blade surface using a material removing method or defined by a calotte situated in a recess in the blade.

11. The blade as recited in claim 1 wherein the blade is a moving blade.

12. The blade as recited in claim 1 wherein the blade is a guide blade.

13. A turbomachine comprising at least one compressor stage and/or turbine stage having at least one blade, the blade comprising: an impact chamber; and a single impulse body movably situated in the impact chamber, a clearance between the impulse body and the impact chamber in ail directions being at least 0.1 mm and at most 1.5 mm and wherein a mass of the impulse body is at least 10 mg and at most 1.5 g.

14. A gas turbine comprising the turbomachine as recited in claim 13.

15. An aircraft engine gas turbine comprising the gas turbine as recited in claim 14.

16. A method for manufacturing a blade as recited in claim 1, the method comprising: providing the impact chamber in the blade; inserting the impulse body into the impact chamber; and subsequently closing the impact chamber.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Other advantages and features are derived from the subclaims and the exemplary embodiments. In partially schematic form:

(2) FIG. 1A shows a shroud area of a blade of a gas turbine according to one embodiment of the present invention, having an opened impact chamber;

(3) FIG. 1B shows an enlarged section of the impact chamber area from FIG. 1A;

(4) FIG. 2A shows a shroud area of a blade of a gas turbine according to another embodiment of the present invention, having an opened impact chamber;

(5) FIG. 2B shows an enlarged section of the impact chamber area from FIG. 2A;

(6) FIG. 3A shows a shroud area of a blade of a gas turbine according to another embodiment of the present invention, having an opened impact chamber;

(7) FIG. 3B shows an enlarged section of the impact chamber area from FIG. 3A;

(8) FIG. 4A shows a perspective view of a blade of a gas turbine according to another embodiment of the present invention, having an opened impact chamber;

(9) FIG. 4B shows an enlarged section of the impact chamber area from FIG. 4A;

(10) FIG. 5A shows a perspective view of a blade of a gas turbine according to another embodiment of the present invention, having an opened impact chamber;

(11) FIG. 5B shows an enlarged section of the impact chamber area from FIG. 5A;

(12) FIG. 6A shows a section of a blade of a gas turbine according to another embodiment of the present invention and an adjacent blade;

(13) FIG. 6B shows an enlarged section of the shroud area of the two adjacent blades from FIG. 6A;

(14) FIG. 7A shows a section of a hollow blade of a gas turbine according to another embodiment of the present invention;

(15) FIG. 7B shows an enlarged detail from FIG. 7A;

(16) FIG. 7C shows a cross section of the impact chamber area from FIG. 7B;

(17) FIG. 8 shows a perspective partial section of a shroud area of a blade of a gas turbine according to another embodiment of the present invention; and

(18) FIG. 9 shows a perspective partial section of a blade root area of a blade of a gas turbine according to another embodiment of the present invention.

DETAILED DESCRIPTION

(19) FIG. 1 shows an outer shroud area of a blade 1 of a gas turbine according to one embodiment of the present invention, including an outer shroud vane having an opened impact chamber, in which a circular disk-shaped impulse body 3 is accommodated. In the operating state of the blade, the impact chamber is closed by a cover 2.1, which is apparent in the enlarged section of the impact chamber area in FIG. 1B, but which is omitted in FIG. 1A.

(20) The impact chamber has an at least essentially cuboid inner contour, which may be primarily shaped or produced using a material removing method, for example milling, for example during casting of the blade. In the section in FIG. 1B, the circular disk-shaped impulse body has a cuboid outer contour. In the section in FIG. 1B, a clearance S1+S2, which is between 10 μm and 1.5 mm, is provided between the outer contour and the parallel side walls. This preferred impact direction is oriented in the direction of a vibrational eigenmode of the blade. In a vertical section perpendicular to the image plane of FIG. 1B, the circular disk-shaped impulse body also has a cuboid outer contour. In this section, in an embodiment in the horizontal direction, a clearance, which is between 10 μm and 1.5 mm, is also provided between the outer contour and the parallel side walls, so that the impulse body has a horizontal degree of freedom in both sections. In another embodiment, however, in the vertical section perpendicular to the image plane of FIG. 1B, a clearance fit is provided in the horizontal direction, which guides the impulse body exclusively in the horizontal preferred impact direction in FIG. 1B. In a horizontal section perpendicular to the image plane of FIG. 1B, the impulse body has a circular disk-shaped outer contour. A clearance fit, which guides the impulse body exclusively in the horizontal direction in FIG. 1B, is provided between the two front sides of the circular disk-shaped impulse body and the sides of the cuboid impact chamber opposite thereto.

(21) The mass of the impulse body manufactured from a nickel or cobalt alloy or ceramic, may be between 10 mg and at most 1.5 g.

(22) After the impact chamber has been provided in the blade and the impulse body has been inserted into this impact chamber, the impact chamber is closed by cover 2.1, which is flush with the outer contour of the blade, as is apparent in FIG. 1B.

(23) During operation, impulse body 3 carries out impacts in the preferred impact directions defined by impact chamber 2, which are determined in this/these direction(s) by the clearance between the impulse body and the impact chamber and which damp blade vibration in a novel way.

(24) FIGS. 2A and 2B show a blade in a way corresponding to FIGS. 1A and 1B according to another embodiment of the present invention. Corresponding elements are identified by the same reference numerals, so that reference is hereby made to the preceding description and only the differences are discussed below.

(25) In the embodiment in FIG. 2, circular disk-shaped impulse body 3 is inserted into the impact chamber not in its radial direction but in its axial direction (upper left to the lower right in FIG. 1B), the latter subsequently being closed by cover 2.1.

(26) FIGS. 3A and 3B show a blade in a way corresponding to FIGS. 1 and 2 according to another embodiment of the present invention. Corresponding elements are identified by the same reference numerals, so that reference is hereby made to the preceding description and only the differences are discussed below.

(27) In the embodiment in FIG. 3, the impulse body and the impulse chamber are situated on the axially inner side of outer shroud vane 1.1.

(28) FIG. 4B shows an enlarged section of the impact chamber area of a blade in a way corresponding to FIGS. 1B, 2B and 3B according to another embodiment of the present invention, which is illustrated in a perspective view in FIG. 4A. Corresponding elements are identified by the same reference numerals, so that reference is hereby made to the preceding description and only the differences are discussed below.

(29) In the embodiment in FIG. 4, impact chamber 2 and impulse body 3 are situated in a blade root 1.2, with the aid of which not only blade 1 but also two additional blades 1′, 1″ are integrally provided.

(30) The impact chamber is closed by the rotor or the hub of the turbomachine (not illustrated) during assembly. FIGS. 5A and 5B show a blade in a way corresponding to FIG. 4 according to another embodiment of the present invention. Corresponding elements are identified by the same reference numerals, so that reference is hereby made to the preceding description and only the differences are discussed below.

(31) In the embodiment in FIG. 5, the impulse body and the impulse chamber are situated on the opposite side of blade root 1.2. The impact chamber may generally be situated on an inlet or outlet side of a blade root.

(32) FIG. 6B shows an enlarged section of the impact chamber area of a blade in a way corresponding to FIGS. 1B, 2B, 3B, 4B and 5B according to another embodiment of the present invention, which is illustrated in a sectional view in FIG. 6A. Corresponding elements are identified by the same reference numerals, so that reference is hereby made to the preceding description and only the differences are discussed below.

(33) In the embodiment in FIG. 6, the impact chamber is not closed by a cover but by an adjacent blade 1′ during assembly.

(34) FIG. 7A shows a section of a blade in a way corresponding to FIG. 6A according to another embodiment of the present invention; FIG. 7B shows an enlarged detail of the impact chamber area in this FIG. 7A; FIG. 7C shows a cross section of this impact chamber area in FIG. 7B.

(35) Blade 1 in FIG. 7 is a hollow blade which includes a turbine blade 1.3 having a cooling channel, in which impact chamber 2 is primarily shaped. During operation, a spherical impulse body 3 is driven by gyroscopic forces into one-sidedly open impact chamber 2, in which it has a clearance S1+S2 in the horizontal direction in FIG. 7B, which is between 10 μm and 1.5 mm.

(36) FIG. 8 shows a blade in a way similar to FIGS. 1 and 3 according to another embodiment of the present invention. Corresponding elements are identified by the same reference numerals, so that reference is hereby made to the preceding description and only the differences are discussed below.

(37) In the embodiment in FIG. 8, impulse body 3 in impact chamber 2 in outer shroud vane 1.1 of blade 1 has a spherical design, the impact chamber being closed by a cover 2.1.

(38) FIG. 9 shows a blade in a way similar to FIGS. 4 and 5 according to another embodiment of the present invention. Corresponding elements are identified by the same reference numerals, so that reference is hereby made to the preceding description and only the differences are discussed below.

(39) In the embodiment in FIG. 9, impulse body 3 in impact chamber 2 in blade root 1.2 of blade 1 also has a spherical design. Impact chamber 2 is also closed by a cover 2.1.

LIST OF REFERENCE NUMERALS

(40) 1, 1′, 1″ Blade 1.1 Outer shroud vane 1.2 Blade root 1.3 Turbine blade 2 Impact chamber 2.1 Cover 3 Impulse body S1+S2 Clearance