Compact advanced passive tip clearance control

Patent metadata

Field	Value
Publication number	US-10344612-B2
Application number	US-201715405778-A
Country	US
Kind code	B2
Filing date	Jan 13, 2017
Priority date	Jan 13, 2017
Publication date	Jul 9, 2019
Grant date	Jul 9, 2019

Abstract

A section of a gas turbine engine includes a rotor blade designed to rotate about an axis. The section also includes a case positioned radially outward from the rotor blade and extending circumferentially about the axis. The section also includes a control ring being annular, positioned radially inward from the case and designed to move radially relative to the case. The section also includes a segmented blade outer air seal (BOAS) including a plurality of BOAS segments each being positioned radially outward from the rotor blade, movably coupled to the control ring, and designed to move circumferentially relative to each other such that a circumferential gap between each of the plurality of BOAS segments changes in size in response to a temperature change in the section of the gas turbine engine.

First claim

What is claimed is:

1. A section of a gas turbine engine, comprising:
a rotor blade configured to rotate about an axis;
a case positioned radially outward from the rotor blade and extending circumferentially about the axis;
a control ring being annular, positioned radially inward from the case, and configured to move radially relative to the case;
a segmented blade outer air seal (BOAS) including a plurality of BOAS segments each being positioned radially outward from the rotor blade, movably coupled to the control ring, and configured to move circumferentially relative to each other such that a circumferential gap between each of the plurality of BOAS segments changes in size in response to a temperature change in the section of the gas turbine engine; and
a circumferential locking tab coupled to the case, slidably coupled to the segmented BOAS, and configured to resist circumferential movement of the segmented BOAS relative to the case.

2. The section of claim 1 , further comprising a spring positioned radially between the segmented BOAS and the control ring and configured to exert a radially inward force on the segmented BOAS towards the rotor blade.

3. The section of claim 1 , wherein the circumferential locking tab defines an annular volume for receiving a portion of the segmented BOAS.

4. The section of claim 1 , wherein the case further includes a spline extending radially inward and the control ring further includes a spline socket configured to receive the spline such that the spline and the spline socket resist axial and circumferential movement of the control ring relative to the case and allow radial movement of the control ring relative to the case.

5. The section of claim 1 , wherein the control ring further includes a pin extending radially outward and the case further includes a pin socket configured to receive the pin such that the pin and the pin socket resist axial and circumferential movement of the control ring relative to the case and allow radial movement of the control ring relative to the case.

6. The section of claim 1 , further comprising at least one flexible arm coupled to the case and the control ring and configured to allow radial movement of the control ring relative to the case.

7. The section of claim 1 , wherein the control ring includes a first foot extending axially forward and a second foot extending axially aftward, and the segmented BOAS includes a first hook extending axially forward and radially outward relative to the first foot and a second hook extending axially aft and radially outward relative to the second foot such that a radial control gap exists between the first foot and the first hook and the segmented BOAS can move radially relative to the control ring by an amount equal to the radial control gap.

8. The section of claim 1 , wherein the control ring includes at least one of a nickel-based alloy or an iron-based alloy.

9. A section of a gas turbine engine, comprising:
a rotor blade configured to rotate about an axis;
a case positioned radially outward from the rotor blade and extending circumferentially about the axis;
a segmented blade outer air seal (BOAS) including a plurality of BOAS segments each being positioned radially outward from the rotor blade, movably coupled to the case, and configured to move circumferentially relative to each other such that a circumferential gap between each of the plurality of BOAS segments changes in size in response to a temperature change in the section of the gas turbine engine; and
a circumferential locking tab coupled to the case, slidably coupled to the segmented BOAS, and configured to resist circumferential movement of the segmented BOAS relative to the case.

10. The section of claim 9 , further comprising a spring positioned radially between the segmented BOAS and the case and configured to exert a radially inward force on the segmented BOAS towards the rotor blade.

11. The section of claim 9 , wherein the case includes a first foot extending axially forward and a second foot extending axially aftward, and the segmented BOAS includes a first hook extending axially forward and radially outward relative to the first foot and a second hook extending axially aft and radially outward relative to the second foot such that a radial control gap exists between the first foot and the first hook and the segmented BOAS can move radially relative to the case by an amount equal to the radial control gap.

12. The section of claim 11 , wherein the first foot and the first hook resist aftward axial movement of the segmented BOAS relative to the case, and the second foot and the second hook resist forward axial movement of the segmented BOAS relative to the case.

13. A gas turbine engine, comprising:
a compressor section configured to compress air;
a combustor section configured to receive compressed air from the compressor section, to combust a mixture of the compressed air and fuel, and to output exhaust; and
a turbine section configured to convert the exhaust into torque to power the compressor section,
wherein at least one of the compressor section or the turbine section include:
a rotor blade configured to rotate about an axis,
a case positioned radially outward from the rotor blade and extending circumferentially about the axis,
a control ring being annular, positioned radially inward from the case, movably coupled to the case, and configured to move radially relative to the case,
a segmented blade outer air seal (BOAS) including a plurality of BOAS segments each being positioned radially outward from the rotor blade, movably coupled to the control ring, and configured to move circumferentially relative to each other such that a circumferential gap between each of the plurality of BOAS segments changes in size in response to a temperature change in the turbine section of the gas turbine engine, and
a circumferential locking tab coupled to the case, slidably coupled to the segmented BOAS, and configured to resist circumferential movement of the segmented BOAS relative to the case.

14. The gas turbine engine of claim 13 , wherein the at least one of the compressor section or the turbine section further includes a spring positioned radially between the segmented BOAS and the control ring and configured to exert a radially inward force on the segmented BOAS towards the rotor blade.

15. The gas turbine engine of claim 13 , wherein the circumferential locking tab defines an annular volume for receiving a portion of the segmented BOAS.

16. The gas turbine engine of claim 13 , wherein the case further includes a spline extending radially inward and the control ring further includes a spline socket configured to receive the spline such that the spline and the spline socket resist axial and circumferential movement of the control ring relative to the case and allow radial movement of the control ring relative to the case.

17. The gas turbine engine of claim 13 , wherein the control ring further includes a pin extending radially outward and the case further includes a pin socket configured to receive the pin such that the pin and the pin socket resist axial and circumferential movement of the control ring relative to the case and allow radial movement of the control ring relative to the case.

18. The gas turbine engine of claim 13 , wherein the at least one of the compressor section or the turbine section further includes at least one flexible arm coupled to the case and the control ring and configured to allow radial movement of the control ring relative to the case.

Assignees

• United Technologies Corp

Inventors

• Hudson Eric A
• Mccaffrey Michael G
• Funk Stanley J
• Virkler Scott D

Classifications

• F04D29/642

  by adjusting the clearances between rotary and stationary parts · CPC title

• F05D2300/171

  Steel alloys · CPC title

• F05D2240/11

  Shroud seal segments · CPC title

• F04D29/324

  Blades · CPC title

• F05D2220/32

  in gas turbines · CPC title