Compressor casing with passive tip clearance control and endwall ovalization control

• US 6,935,836 B2
• Filed: 06/05/2003
• Issued: 08/30/2005
• Est. Priority Date: 06/05/2002
• Status: Expired due to Term

• Current Assignee: Rolls-Royce North American Technologies Incorporated
• Original Assignee: Rolls-Royce North American Technologies Incorporated
• Inventors: King, Brian, Ress, Robert Anthony Jr.
• Primary Examiner(s): Lopez, F. Daniel
• Assistant Examiner(s): Edgar, Richard A.
• Application Number:
  US10/455,693
• Publication Number:
  US 20050031446A1
• Time in Patent Office: 817 Days
• Field of Search: 415/170.1, 415/173.1, 415/173.2, 415/173.7, 415/173.3, 415/173.4, 415/174.1, 415/174.2, 415/174.4, 415/209.2
• US Class Current: 415/173.2
• CPC Class Codes: F01D 11/025 Seal clearance control; Floating assembly; Adaptation means to differential thermal dilatations
• CPC Class Codes: F01D 11/16 by self-adjusting means F01D11/12 takes precedence
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

A passive clearance control system for a gas turbine engine component. The system provides a blade shroud that is isolated from the component case and can move radially to maintain blade clearance. A plurality of vane sectors define a stator ring including a blade shroud. The stator ring and the control ring are coupled together and mounted within the component by a plurality of radial extending mounting members.

Claims

1. A gas turbine engine apparatus, comprising:

a mechanical housing;

a first rotor with a plurality of first blades located within said mechanical housing and rotatable about a centerline, each of said plurality of first blades including a first tip;

a control ring located within and spaced from said mechanical housing;

a plurality of locating members fixedly coupled with said mechanical housing and slidably coupled with said control ring, said plurality of locating members positioning said control ring relative to said mechanical housing;

a non-rotatable ring with a plurality of vanes located within said mechanical housing and axially spaced from said first rotor, wherein said non-rotatable ring includes a tip shroud portion spaced from said first tips of said plurality of first blades, and wherein said non-rotatable ring is fixedly coupled with said control ring and moveable therewith; and

wherein relative motion may occur between said control ring and at least one of said plurality of locating members.

2. The apparatus of claim 1, wherein said control ring includes a fore end and an aft end, and wherein said non-rotatable ring includes an engagement portion that engages with one of said fore end and said aft end.

3. The apparatus of claim 2, wherein said engagement portion includes a circular rail arrangement that mates with one of said fore end and said aft end.

4. The apparatus of claim 1, wherein said mechanical housing includes a flowpath, and which further includes means for exposing said control ring to working fluid from said flowpath.

5. The apparatus of claim 1, wherein said control ring includes at least one circumferential stiffening rib.

6. The apparatus of claim 1, wherein each of said plurality of locating members extending inwardly in a radial orientation from said mechanical housing, and wherein said relative motion is in a radial direction.

7. The apparatus of claim 6, wherein each of said plurality of locating members includes a threaded portion that attaches with said mechanical housing to fixedly couple said locating member with said mechanical housing, and wherein each of said locating members include a pilot portion that allows for relative sliding movement between said control ring and said pilot portion.

8. The apparatus of claim 1, wherein said non-rotatable ring is formed of a plurality of adjacent vane sectors, wherein each of said plurality of vane sectors defines an arc of about 30°

to about 60°

, and wherein said control ring is an integral 360°

ring.

9. The apparatus of claim 1, wherein said control ring includes a fore end and an aft end;

wherein said non-rotatable ring includes a circular rail engagement portion that mates with one of said fore end and said aft end;

which further includes a plurality of fasteners, wherein said plurality of fasteners attach said non-rotatable ring to said control ring proximate said engagement portion;

wherein each of said plurality of locating members extending inwardly in a radial direction from said mechanical housing; and

wherein said relative motion is in a substantially radial direction.

10. The apparatus of claim 9, wherein said non-rotatable ring is formed from a plurality of adjacent vane sectors, and wherein each of said plurality of locating members includes a threaded portion that engages with said mechanical housing to fixedly couple said locating member with said mechanical housing, and wherein each of said locating members includes a pilot portion that allows relative sliding movement between said control ring and said pilot portion.

11. A gas turbine engine apparatus, comprising:

a case;

a rotatable first rotor with a plurality of circumferentially spaced first blades located within said case and about a centerline, each of said plurality of first blades including a first tip;

a control ring located within and spaced radially from said case;

a plurality of radial mounting members fixedly connected with said case, each of said plurality of radial mounting members extending radially and slidably engaging an opening in said control ring, wherein said plurality of locating members positioning said control ring relative to case; and

a plurality of vane sectors mounted in a substantially adjacent relationship within said case to form a non-rotatable ring axially spaced from said first rotor, each of said plurality of vane sectors includes an inner endwall and an outer endwall with at least one vane located between said endwalls, wherein each of said outer endwalls has an extension member extending therefrom including a shroud portion and a coupling portion, wherein each of said shroud portions extending along and spaced radially from said first tips and each of said coupling portions fixedly coupled with said control ring, and said plurality of vane sectors and said control ring are moveable together, and

wherein relative radial motion may occur between at least one of said radial mounting members and said control ring.

12. The apparatus of claim 11, wherein said plurality of radial mounting members substantially prevents axial movement of said control ring and said non-rotatable ring, and wherein said case is a horizontally split case.

13. The apparatus of claim 11, wherein said control ring includes a first engagement portion and a second engagement portion, and wherein each of said coupling portions engage with one of said engagement portions;

and

which further includes a plurality of fasteners that hold said control ring to said non-rotatable ring.

14. The apparatus of claim 13, wherein each of said shroud portions includes an abradable coating;

wherein each of said plurality of vane sectors defines an arc between about 30° and

about 60°

.

15. The apparatus of claim 14, wherein said plurality of radial mounting members are spaced around the periphery of said case at a constant axial position;

and

wherein said radial mounting members include a threaded portion for engaging said case and an extension portion that is slideable relative to said opening in said control ring.

16. The apparatus of claim 11, wherein said control ring includes a plurality of axial spaced circumferentially extending stiffening ribs.

17. The apparatus of claim 11, wherein said case is a horizontally split case having a flowpath for a working fluid;

which further includes a bleed to acquire a quantity of working fluid from said flowpath and direct the quantity of working fluid across said control ring;

wherein said control ring includes a first engagement portion and a second engagement portion, and wherein each of said coupling portions engage with one of said engagement portions;

which further includes a plurality of fasteners that hold said control ring to said non-rotatable ring; and

wherein each of said vane sectors define an arc between about 30° and

about 60°

.

18. The apparatus of claim 17, which further includes means for controlling the flow of the quantity of working fluid from said flowpath and across said control ring.

19. The apparatus of claim 11, wherein said case includes a flowpath, and which further includes means for exposing said control ring to working fluid from said flowpath.

20. A compressor passive clearance control system, comprising:

a compressor case having a flowpath for working fluid flow;

a rotatable first rotor with a plurality of circumferentially spaced first blades located within said case and about a centerline, each of said plurality of first blades is disposed within said flowpath and includes a first tip;

a rotatable second rotor with a plurality of circumferentially spaced second blades located within said case and about said centerline, each of said plurality of second blades is disposed within said flowpath and includes a second tip;

a control ring located within said case;

a plurality of radial mounting members fixedly connected with said case, each of said plurality of radial mounting members extending radially and slidably engaging an opening in said control ring, wherein said plurality of locating members positioning said control ring relative to case; and

a plurality of vane sectors mounted in a substantially adjacent relationship within said case to form a non-rotatable ring axially spaced from said first rotor, each of said plurality of vane sectors includes an inner endwall and an outer endwall with at least one vane located between said endwalls and within said flowpath, wherein each of said outer endwalls has a fore extension member and an aft extension member, said fore extension member extending from said outer endwall and including a fore shroud portion and a fore coupling portion, wherein each of said fore shroud portions extending along and spaced radially from said first tips and each of said fore coupling portions fixedly coupled with a first portion of said control ring, and wherein said aft extension member extending from said outer endwall and including an aft shroud portion and an aft coupling portion, wherein each of said aft shroud portions extending along and spaced radially from said second tips and each of said aft coupling portions fixedly coupled with a second portion of said control ring, and said plurality of vane sectors and said control ring arc moveable together,

a working fluid bleed to direct a portion of working fluid from said flowpath across said control ring; and

wherein relative radial motion may occur between at least one of said radial mounting members and said control ring.

21. The system of claim 20, wherein relative radial motion may occur between each of said plurality of radial mounting members and said control ring.

22. The system of claim 21, wherein each of said plurality of radial mounting members is connected with said case by threads, and each of said plurality of radial mounting members include a pilot portion that is disposed in a sliding non-interference fit with said opening in said control ring.