Profiled structure for an aircraft or turbomachine

Patent metadata

Field	Value
Publication number	US-11668196-B2
Application number	US-201917286751-A
Country	US
Kind code	B2
Filing date	Sep 24, 2019
Priority date	Oct 18, 2018
Publication date	Jun 6, 2023
Grant date	Jun 6, 2023

Abstract

A profiled structure for an aircraft or turbomachine is elongated in a direction in which the structure has a length exposed to an airflow and includes serrations defined by successive teeth and depressions. The serrations may be transverse to a leading edge and/or a trailing edge of the profiled structure and in the direction of elongation. Along the profiled leading edge and/or profiled trailing edge, the successive teeth and depressions may extend only over a part of the length exposed to the flow. The amplitude and/or spacing of the teeth may vary monotonically except for the few teeth nearest each end of the part, with a remaining part of the length being smooth.

First claim

The invention claimed is:

1. A profiled structure for an aircraft or for a turbomachine of an aircraft,
which is elongated in a direction of elongation in which the profiled structure has a length exposed to an airflow, and
which has a leading edge and/or a trailing edge, at least one of which being profiled, wherein the profiled leading edge and/or the profiled trailing edge has, along said direction of elongation, serrations defined by successive teeth and depressions extending transversely with respect to the direction of elongation,
wherein, along the profiled leading edge and/or the profiled trailing edge:
the successive teeth and depressions extend over only a part of said length exposed to the airflow, a remaining part of said length being smooth, and
over said part of the length, with the exception of zones comprising at most three successive teeth located at each of two ends of said part of the length, the serrations have variations in amplitude and/or in spacing between two successive vertices of teeth or of depressions, said variations being monotonic, and,

wherein, over at least a part of said length where serrations are present, the amplitude and/or the spacing between two successive vertices of teeth or vertices of depressions varies linearly, or quadratically, or hyperbolically, or exponentially, or logarithmically, wherein the varying occurs over three or more amplitudes and/or three or more spacings, respectively.

2. The profiled structure according to claim 1 wherein, over at least part of the length exposed to the airflow where serrations are present and, either with reference to an average chord or for each chord at each serration along said direction, these serrations comply, transversely to the direction of elongation, with the relationship: 0.005≤d/c≤0.5, with: “d” being the amplitude of the serrations in meters and “c” being the chord of the profiled structure, at a location of said serrations, in meters.

3. The profiled structure according to claim 2 in which, along the profiled leading edge and/or profiled trailing edge and by variation in amplitude and/or spacing between two successive vertices of teeth or of depressions, the serrations progressively join said smooth part of the length.

4. The profiled structure according to claim 3 , wherein the serrations terminate in a joint that is tangent to said smooth part.

5. The profiled structure according to claim 2 , wherein the serrations terminate in a joint that is tangent to said smooth part.

6. The profiled structure according claim 2 wherein, on said smooth part of the length, said structure has a chord longer than the chord is at any vertex of any of said depressions.

7. The profiled structure according to claim 1 in which, along the profiled leading edge and/or profiled trailing edge and by variation in amplitude and/or spacing between two successive vertices of teeth or of depressions, the serrations progressively join said smooth part of the length.

8. The profiled structure according to claim 7 , wherein the serrations terminate in a joint that is tangent to said smooth part.

9. The profiled structure according claim 7 wherein, on said smooth part of the length, said structure has a chord longer than the chord is at any vertex of any of said depressions.

10. The profiled structure according to claim 1 , wherein the serrations terminate in a joint that is tangent to said smooth part.

11. The profiled structure according claim 1 wherein, on said smooth part of the length, said structure has a chord longer than the chord is at any vertex of any of said depressions.

12. The profiled structure according to claim 1 in which, over said part of the length, with the exception of said zones, a series of at least three consecutive teeth and three consecutive depressions has a strictly increasing distance, along said direction of elongation, between two consecutive vertices of teeth or of depressions.

13. The profiled structure according to claim 1 wherein, over said part of the length, with the exception of said zones, a series of at least three consecutive teeth and three depressions has a strictly increasing amplitude.

14. The profiled structure according to claim 1 wherein, along said length exposed to the air flow, the serrations are absent:
at at least one of the two ends of said length, or
at an intermediate part between said ends and present towards said two ends.

15. The profiled structure according to claim 1 wherein, over at least a part of said length where serrations are present, the amplitude and/or the spacing between two successive vertices of teeth or of depressions varies non-periodically.

16. A set of profiled structures, each according to claim 1 , whose respective directions of elongation extend radially about an axis of revolution, and whose distance between two successive vertices of teeth or of depressions and/or the amplitude is longer at a radially outer end of the length exposed to an airflow than at a radially inner end of that length.

17. A turbomachine having a general axis and comprising a rotor, rotatable about said general axis, and a stator, the stator and/or rotor comprising profiled structures, each according to claim 1 .

18. The turbomachine of claim 17 , wherein the profiled structure is located:
on an annular separating wall for separating an air flow downstream of a fan of the turbomachine between a primary flow and a secondary flow,
or on an outlet guide vane (OGV),
or on an inlet guide vane (IGV).

19. A profiled structure for an aircraft or for a turbomachine of an aircraft,
which is elongated in a direction of elongation in which the profiled structure has a length exposed to an airflow, and
which has a leading edge and/or a trailing edge, at least one of which being profiled, wherein the profiled leading edge and/or the profiled trailing edge has, along said direction of elongation, serrations defined by successive teeth and depressions extending transversely with respect to the direction of elongation,
wherein, along the profiled leading edge and/or the profiled trailing edge:
the successive teeth and depressions extend over only a part of said length exposed to the airflow, a remaining part of said length being smooth, and
over said part of the length, with the exception of zones comprising at most three successive teeth located at each end of said part of the length, the serrations have variations in amplitude and/or in spacing between two successive vertices of teeth or of depressions, said variations being monotonic,

wherein, over at least said part of the length, the amplitude and/or the spacing between two successive vertices of teeth or vertices of depressions varies linearly, or quadratically, or hyperbolically, or exponentially, or logarithmically, wherein the varying occurs over three or more amplitudes and/or three or more spacings, respectively, and,
wherein, along said length exposed to the air flow, the serrations are absent:
at several places along said length separated from each other, or
at an intermediate part between said ends and present towards said two ends.

20. A profiled structure for an aircraft or for a turbomachine of an aircraft,
which is elongated in a direction of elongation in which the profiled structure has a length exposed to an airflow, and
which has a leading edge and/or a trailing edge, at least one of which being profiled,
wherein the profiled leading edge and/or the profiled trailing edge has, along said direction of elongation, se

Assignees

• Safran Aircraft Engines
• Office National Detudes Rech Aerospatiales

Inventors

• Gea Aguilera Fernando
• Barrier Raphaël
• Gruber Mathieu Simon Paul
• Polacsek Cyril
• Posson Hélène Dominique Jeanne

Classifications

• F05D2220/323

  for aircraft propulsion, e.g. jet engines · CPC title

• F05D2240/121

  related to the leading edge of a stator vane · CPC title

• F01D5/145 Primary

  Means for influencing boundary layers or secondary circulations (for compressors F04D29/68) · CPC title

• Y02T50/10

  Drag reduction · CPC title

• B64C3/10

  Shape of wings · CPC title