Arrangement for reducing oscillation

Patent metadata

Field	Value
Publication number	US-11898618-B2
Application number	US-202217743474-A
Country	US
Kind code	B2
Filing date	May 13, 2022
Priority date	May 20, 2021
Publication date	Feb 13, 2024
Grant date	Feb 13, 2024

Abstract

An arrangement reduces oscillation of an oscillatory structure. The arrangement has: a structure having at least one mode in at least one direction; and an oscillation-reducing device. The oscillation-reducing device includes a housing on the structure; a cavity; and a body. The body is configured to make impact contact with a first surface portion and a second surface portion of an inner wall of the housing and disposed is in the cavity such that the body can make impact contact with the first surface portion and the second surface portion of the inner wall of the housing at least temporarily for as long as the structure is excited in the at least one mode in the at least one direction. The first surface portion or the second surface portion of the inner wall of the housing has a curved profile.

First claim

The invention claimed is:

1. An arrangement for reducing oscillation of an oscillatory structure, the arrangement comprising:
a structure having at least one mode in at least one direction; and
at least one oscillation-reducing device comprising at least one housing formed by or provided on the structure; a cavity having only one body disposed therein; the body being configured to make substantially elastic impact contacts with a first surface portion and a second surface portion of an inner wall of the housing and disposed in the cavity in such a manner that the body is configured to make impact contacts with the first surface portion and the second surface portion of the inner wall of the housing at least temporarily for as long as the structure is excited in the at least one mode in the at least one direction,
wherein the first surface portion and the second surface portion of the inner wall of the housing each have a respective curved profile,
wherein the first surface portion and the second surface portion are opposite each other and a line between a center of the respective curve profile for each of the first surface and the second surface extends in a first direction,
wherein dimensions of the cavity confine a movement direction of the body to be parallel to the first direction.

2. The arrangement as recited in claim 1 , wherein the body is a sphere having a radius R is, and wherein for a curvature k of the curved profile.

-

1
R

≤
k
≤

1
R

.

3. The arrangement as recited in claim 2 , wherein k≠0.

4. The assembly as recited in claim 2 , wherein:

k
=

-

1
R

,

or

k
=

1
R

.

5. The arrangement as recited in claim 1 , wherein a third surface portion of the inner wall extending parallel to the at least one direction is a planar surface portion.

6. The arrangement as recited in claim 1 , wherein the oscillation-reducing device is configured to reduce a maximum oscillation amplitude in the at least one mode by at least 5%, 20%, 30%, 40% or 50% compared to the oscillation amplitude in the at least one mode without the oscillation-reducing device.

7. The arrangement as recited in claim 1 , wherein the structure is at least a part or a portion of a gas turbine, of a motor, of a turbine, of a manufacturing machine, of a propulsion system, of a construction, or of a vehicle, a part in contact therewith, or a portion in contact therewith.

8. The arrangement as recited in claim 1 , wherein a total mass of the body is at least 100 times smaller than the structure's modal mass that oscillates in the respective mode or the modal mass oscillating in the respective mode is no more than 200000 times greater than the total mass of the at least one body.

9. The arrangement as recited in claim 1 , wherein the at least one oscillation-reducing device is disposed on the structure only in those regions where the oscillation amplitude in the at least one mode without the oscillation-reducing device in the respective region is at least 0.1%, or no more than 100% of the maximum oscillation amplitude in the at least one mode without the oscillation-reducing device in the respective region.

10. The arrangement as recited in claim 1 , wherein a clearance for movement of the body in the movement direction is no more than 2 times a maximum cross-sectional dimension of the body or at least 0.05 times the maximum cross-sectional dimension of the body.

11. The arrangement as recited in claim 1 , wherein the body has a metallic or ceramic surface, and the first surface portion or the second surface portion of the inner wall of the housing is a metallic surface or a ceramic surface, so that the impact contacts occur between metal and metal, between ceramic and ceramic, or between metal and ceramic.

12. The arrangement as recited in claim 1 , wherein one of the first and second surface portions is convexly or concavely curved, and the other of the first and second surface portions is convexly or concavely curved.

13. The arrangement as recited in claim 1 , wherein the cavity is a closed cavity and the body is configured to make impact contacts with the first surface portion and the second surface portion of the inner wall of the housing at continuously for as long as the structure is excited in the at least one mode in the at least one direction.

14. The arrangement as recited in claim 1 , wherein the at least one body is a sphere having a radius R is, and wherein for a curvature k of the curved profile, − 1 /R≤k≤− 1 / 4 R or 1 / 4 R≤k≤ 1 /R.

15. The arrangement as recited in claim 1 ,
wherein the cavity is one of a plurality of cavities,
wherein the body is one of a plurality of bodies, each of the bodies assigned to a respective one of the cavities,
wherein a total mass of all of the bodies of the oscillation-reducing device is at least 100 times smaller than the structure's modal mass that oscillates in the respective mode or the modal mass oscillating in the respective mode is no more than 200000 times greater than the total mass of all of the bodies.

16. The arrangement as recited in claim 1 ,
wherein the cavity is one of a plurality of cavities,
wherein the body is one of a plurality of bodies, each of the bodies assigned to a respective one of the cavities, and
wherein for each of the bodies in the respective one of the cavities, a clearance for movement of body in all directions is no more than 2 times a maximum cross-sectional dimension of the bodies or at least 0.05 times the particular maximum cross-sectional dimension of the body.

17. The arrangement as recited in claim 5 , wherein a fourth surface portion of the inner wall extending parallel to the at least one direction is a planar surface portion, and wherein a gap between the third surface and fourth surface is configured so as to confine the body to movement in the movement direction.

18. The arrangement of claim 17 , wherein the respective curve profile for each of the first surface and the second surface is concave.

19. The arrangement of claim 1 , wherein the first direction comprises with the at least one direction of the mode.

Assignees

• MTU Aero Engines AG

Inventors

• Hartung Andreas
• Schlemmer Markus
• Krack Malte
• Theurich Timo

Classifications

• F05D2250/711

  convex · CPC title

• F05D2250/241

  spherical · CPC title

• F01D5/10

  Anti- vibration means {(specially adapted for radial flow machines or engines F01D5/04)} · CPC title

• F01D25/06

  for preventing blade vibration (means on blade-carrying members or blades F01D5/00) · CPC title

• F01D5/26

  Antivibration means not restricted to blade form or construction or to blade-to-blade connections {or to the use of particular materials} · CPC title