Aerofoil structure for a gas turbine engine

Patent metadata

Field	Value
Publication number	US-2025250900-A1
Application number	US-202418926997-A
Country	US
Kind code	A1
Filing date	Oct 25, 2024
Priority date	Nov 21, 2023
Publication date	Aug 7, 2025
Grant date	—

Abstract

An aerofoil structure for a gas turbine engine includes an aerofoil portion and a tip portion. The tip portion includes a tip surface configured to face a corresponding seal segment of the gas turbine engine and a plurality of cutting features provided on at least a portion of the tip surface. The cutting features are discrete and spaced apart from each other. The tip surface defines a longitudinal axis along a length of the tip surface and a transverse axis perpendicular to the longitudinal axis. Each cutting feature extends from the tip surface and is configured to cut into the seal segment in a cutting direction parallel to the longitudinal axis upon rotation of the aerofoil structure relative to the seal segment. A minimum longitudinal distance between a pair of adjacent cutting features from the plurality of cutting features along the longitudinal axis is at least 100 microns.

First claim

We claim:

1 . An aerofoil structure for a gas turbine engine, the aerofoil structure comprising:
an aerofoil portion and a tip portion, the tip portion comprising a tip surface configured to face a corresponding seal segment of the gas turbine engine and a plurality of cutting features provided on at least a portion of the tip surface, wherein the cutting features are discrete and spaced apart from each other, the tip surface defining a longitudinal axis along a length of the tip surface and a transverse axis perpendicular to the longitudinal axis, each cutting feature from the plurality of cutting features extending from the tip surface and being configured to cut into the seal segment in a cutting direction parallel to the longitudinal axis upon rotation of the aerofoil structure relative to the seal segment, wherein a minimum longitudinal distance between a pair of adjacent cutting features from the plurality of cutting features along the longitudinal axis is at least 100 microns.

2 . The aerofoil structure of claim 1 , wherein the minimum longitudinal distance is from 100 microns to 200 microns.

3 . The aerofoil structure of claim 1 , wherein a minimum transverse distance between a pair of adjacent cutting features from the plurality of cutting features along the transverse axis is from 80 microns to 280 microns.

4 . The aerofoil structure of claim 1 , wherein a pair of adjacent cutting features from the plurality of cutting features that are spaced apart from each other along the longitudinal axis define a minimum overlap between them along the transverse axis, and wherein the minimum overlap is at least 10 microns.

5 . The aerofoil structure of claim 1 , wherein each cutting feature defines a maximum width along the transverse axis, and wherein the maximum width is from 100 microns to 300 microns.

6 . The aerofoil structure of claim 1 , wherein each cutting feature defines a maximum length along the longitudinal axis, and wherein the maximum length is from 100 microns to 200 microns.

7 . The aerofoil structure of claim 1 , wherein each cutting feature defines a maximum height from and perpendicular to the tip surface, and wherein the maximum height is from 75 microns to 250 microns.

8 . The aerofoil structure of claim 7 , wherein at least two cutting features from the plurality of cutting features have different maximum heights from the tip surface.

9 . The aerofoil structure of claim 1 , wherein each cutting feature comprises a leading surface extending from the tip surface, a trailing surface spaced apart from the leading surface along the longitudinal axis and extending from the tip surface, and a top surface spaced apart from the tip surface and extending between the leading surface and the trailing surface, the leading surface and the top surface intersecting at a cutting tip that is configured to first cut the seal segment in the cutting direction.

10 . The aerofoil structure of claim 9 , wherein a rake angle between the leading surface and a normal axis perpendicular to the tip surface is from 90 degrees to −50 degrees.

11 . The aerofoil structure of claim 9 , wherein a relief angle between the top surface and the longitudinal axis is from 10 degrees to 30 degrees.

12 . The aerofoil structure of claim 1 , wherein the plurality of cutting features is arranged in a plurality of rows extending along the transverse axis and spaced apart from each other along the longitudinal axis.

13 . The aerofoil structure of claim 12 , wherein adjacent rows from the plurality of rows are staggered from each other along the transverse axis.

14 . The aerofoil structure of claim 13 , wherein the cutting features of at least two rows from the plurality of rows are vertically offset from each other along a normal axis perpendicular to the tip surface.

15 . The aerofoil structure of claim 1 , wherein the aerofoil structure further comprises a coating disposed on the plurality of cutting features.

16 . The aerofoil structure of claim 15 , wherein the coating comprises a material having a higher hardness than a material of each cutting feature.

17 . A method of manufacturing the aerofoil structure of claim 1 , the method comprising forming the plurality of cutting features on the tip surface by at least one of: electrical discharge machining, electro chemical machining, machining, milling, stamping, casting, mechanical blasting, chemical etching, and laser ablation.

18 . A gas turbine engine including the aerofoil structure of claim 1 .

19 . The gas turbine engine of claim 18 , further comprising a seal segment comprising an abradable coating facing the tip surface of the aerofoil structure, wherein each cutting feature of the aerofoil structure is configured to cut the abradable coating.

Assignees

• Rolls Royce Plc

Inventors

• Long Kevin
• Hancock Matthew
• NOVOVIC Donka

Classifications

• F01D11/122

  with erodable or abradable material (blades having cutting or grinding tips F01D5/20) · CPC title

• F01D5/288

  Protective coatings for blades · CPC title

• F05D2230/11

  by electrochemical methods · CPC title

• F05D2230/13

  using lasers · CPC title

• F05D2240/307

  related to the tip of a rotor blade · CPC title