Encapsulated flow mixer stiffener ring

Patent metadata

Field	Value
Publication number	US-11073103-B2
Application number	US-201916250325-A
Country	US
Kind code	B2
Filing date	Jan 17, 2019
Priority date	Feb 14, 2018
Publication date	Jul 27, 2021
Grant date	Jul 27, 2021

Abstract

An exhaust mixer arrangement for a gas turbine engine comprises an exhaust cone, a lobed exhaust mixer surrounding at least a portion of the exhaust cone and a cover mounted to an outer surface of the exhaust cone. The cover and the outer surface of the exhaust cone define a dead-end cavity for receiving a stiffener ring. A plurality of circumferentially spaced-apart struts interconnect at least a number of lobes of the lobed exhaust mixer to the stiffener ring.

First claim

The invention claimed is:

1. An exhaust mixer arrangement configured to be mounted at an exhaust of a gas turbine engine, comprising:
an exhaust cone;
a lobed exhaust mixer surrounding at least a portion of the exhaust cone;
a cover mounted to an outer surface of the exhaust cone, the cover and the outer surface of the exhaust cone defining a dead-end cavity therebetween, the cover including an annular cover plate having circumferentially spaced-apart slots defined therein;
a stiffener ring disposed in the dead-end cavity; and
a plurality of circumferentially spaced-apart struts interconnecting a plurality of lobes of the lobed exhaust mixer to the stiffener ring, the plurality of circumferentially spaced-apart struts extending through the circumferentially spaced-apart slots, the circumferentially spaced-apart slots having axially open ends defined in an upstream edge of the annular cover plate.

2. The exhaust mixer arrangement defined in claim 1 , wherein the cover has an outer surface defining a portion of an inner flow boundary wall of a gas path configured for receiving exhaust gases from a turbine section of the gas turbine engine, the cover shielding the stiffener ring from the gas path.

3. The exhaust mixer arrangement defined in claim 1 , wherein the cover is mounted over a step formed on the outer surface of the exhaust cone.

4. The exhaust mixer arrangement defined in claim 1 , where in the exhaust cone has a hollow internal volume, and wherein the dead-end cavity is disposed outside of the hollow internal volume.

5. The exhaust mixer arrangement defined in claim 1 , wherein the circumferentially spaced-apart slots have an axially elongated profile including a main oblong portion and an entry guiding portion, the entry guiding portion having a width which is less than a width of the main oblong portion, the entry guiding portion further having an axial length which is less than an axial length of the main oblong portion.

6. A gas turbine engine comprising:
a main gaspath having an inner flow boundary wall and an outer flow boundary wall;
a turbine exhaust case inner body having an outer surface defining a portion of the inner flow boundary wall of the main gaspath;
a lobed exhaust mixer surrounding at least a portion of the turbine exhaust case inner body and defining a portion of the outer flow boundary wall of the main gaspath;
an annular cover plate mounted to the turbine exhaust case inner body;
a cavity between the annular cover plate and the outer surface of the turbine exhaust case inner body;
a stiffener ring disposed in the cavity radially inward from the annular cover plate relative to a longitudinal axis of the gas turbine engine; and
a series of circumferentially spaced-apart struts interconnecting a plurality of lobes of the lobed exhaust mixer to the stiffener ring, the series of circumferentially spaced-apart struts extending radially through corresponding slots defined in the annular cover plate, the series of circumferentially spaced-apart slots having axially open ends defined in an upstream edge of the annular cover plate.

7. The gas turbine engine defined in claim 6 , wherein the annular cover plate has an outer surface defining a portion of the inner flow boundary wall of the main gaspath, the annular cover plate shielding the stiffener ring from the main gaspath.

8. The gas turbine engine defined in claim 6 , wherein the annular cover plate is mounted over a step formed in the turbine exhaust case inner body.

9. The gas turbine engine defined in claim 6 , wherein the turbine exhaust case inner body includes an exhaust cone having a hollow internal volume, and wherein the cavity is disposed outside of the hollow internal volume.

10. The gas turbine engine defined in claim 6 , wherein the slots have an axially elongated profile including a main oblong portion and an entry guiding portion, the entry guiding portion having a width which is less than a width of the main oblong portion, the entry guiding portion further having an axial length which is less than an axial length of the main oblong portion.

11. A gas turbine engine comprising: an engine casing enclosing a compressor section, a combustor and a turbine section defining a main gaspath serially extending therethrough, the main gaspath having an inner flow boundary wall and an outer flow boundary wall, the gas turbine engine further comprising:
a turbine exhaust case inner body having an outer surface defining a portion of the inner flow boundary wall of the main gaspath;
an exhaust mixer connected to an aft end of the engine casing and surrounding at least a portion of the turbine exhaust case inner body, the exhaust mixer having a mixer body forming a portion of the outer flow boundary wall of the main gaspath and defining a plurality of circumferentially distributed alternating inner and outer lobes;
an annular cover plate mounted to the outer surface of the turbine exhaust case inner body, the annular cover plate having a radially outer surface forming a portion of the inner flow boundary wall of the main gaspath;
a stiffener ring located radially between the annular cover plate and the outer surface of the turbine exhaust case inner body; and
a series of circumferentially spaced-apart struts which radially extend through the main gaspath between at least some of the inner lobes and the stiffener ring, the series of circumferentially spaced-apart struts extending though individual slots defined in the annular cover plate, the series of circumferentially spaced-apart slots having axially open ends defined in an upstream edge of the annular cover plate.

12. The gas turbine engine defined in claim 11 , wherein the annular cover plate cooperates with the outer surface of the turbine exhaust case inner body to define a dead-end cavity therebetween, the stiffener ring received in the dead-end cavity.

13. The gas turbine engine defined in claim 11 , wherein the annular cover plate is mounted over a step formed in the turbine exhaust case inner body.

14. The gas turbine engine defined in claim 12 , wherein the turbine exhaust case inner body includes an exhaust cone having a hollow internal volume, and wherein the dead-end cavity is disposed outside of the hollow internal volume.

15. The gas turbine engine defined in claim 11 , wherein the slots have an axially elongated profile including a main oblong portion and an entry guiding portion, the entry guiding portion having a width which is less than a width of the main oblong portion, the entry guiding portion further having an axial length which is less than an axial length of the main oblong portion.

Assignees

• Pratt & Whitney Canada

Inventors

• Boyer Philippe
• Coutu Daniel

Classifications

• F05D2250/611

  undulated · CPC title

• F02K1/386 Primary

  mixing devices in the jet pipe, e.g. for mixing primary and secondary flow · CPC title

• F02K1/78

  Other construction of jet pipes · CPC title

• F05D2300/50212

  dissimilar · CPC title

• F05D2260/96

  Preventing, counteracting or reducing vibration or noise · CPC title