Heat shield based air dam for a turbine exhaust case

Patent metadata

Field	Value
Publication number	US-9976442-B2
Application number	US-201314441521-A
Country	US
Kind code	B2
Filing date	Dec 18, 2013
Priority date	Dec 29, 2012
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

A turbine exhaust case employed in an industrial gas turbine engine includes a frame, a fairing and a heat shield. The frame includes an outer ring, an inner ring, and struts connected between the outer ring and the inner ring. The fairing includes a fairing outer ring, a fairing inner ring, and fairing struts connected between the fairing outer ring and the fairing inner ring. The heat shield is located between the frame outer ring and the fairing outer ring and provides a thermal barrier between the fairing outer ring and the frame outer ring, wherein the heat shield includes an aft portion having a flange that interfaces with the frame outer ring to form an air dam that directs cooling airflow forward along the frame outer ring within an outer diameter cavity formed between the frame outer ring and the heat shield.

First claim

The invention claimed is:

1. A turbine exhaust case (TEC) employed in an industrial gas turbine engine, the turbine exhaust case comprising:
a frame having a frame outer ring, a frame inner ring, and a plurality of hollow frame struts connected between the outer ring and the inner ring, wherein the hollow frame struts include a plurality of fluid carrying apertures;
a fairing having a fairing outer ring, a fairing inner ring, and a plurality of fairing struts connected between the fairing outer ring and the fairing inner ring; and
a heat shield located between the frame outer ring and the fairing outer ring that provides a thermal barrier between the fairing outer ring and the frame outer ring, wherein the heat shield includes an aft portion having a flange that interfaces with the frame outer ring to form an air dam that directs cooling airflow forward along the frame outer ring within an outer diameter (OD) cavity formed between the frame outer ring and the heat shield;
wherein the plurality of fluid carrying apertures are configured to carry fluid from a hollow portion of the frame strut and are located proximal an outer diameter cavity between the heat shield and the frame outer ring.

2. The turbine exhaust case of claim 1 , wherein the heat shield includes a plurality of metering holes that direct a desired amount of cooling airflow aft towards an aft seal.

3. The turbine exhaust case of claim 2 , wherein the plurality of metering holes are of equal size.

4. The turbine exhaust case of claim 2 , wherein the plurality of metering holes include metering holes of at least two different sizes.

5. The turbine exhaust case of claim 2 , wherein the plurality of metering holes are equally spaced circumferentially around the heat shield.

6. The turbine exhaust case of claim 1 , wherein the heat shield further includes a second air dam for directing the cooling airflow discharged by the hollow strut into the OD cavity.

7. The turbine exhaust case of claim 6 , wherein the second air dam includes a first portion located aft of the hollow strut.

8. The turbine exhaust case of claim 7 , wherein the second air dam includes a second portion and third portion located on either side of the hollow strut and formed integral with the first portion to direct the cooling airflow discharged by the hollow strut forward.

9. The turbine exhaust case of claim 8 , further including a third air dam located forward of the hollow strut, but not adjacent to the second and third air dam portions to provide a passageway for directing cooling airflow forward and circumferentially around the OD cavity.

10. The turbine exhaust case of claim 1 , wherein the plurality of fluid carrying apertures are positioned to expel airflow circumferentially outward from the hollow frame struts.

11. A heat shield disposed in an outer diameter (OD) cavity between a frame outer ring and a fairing outer ring, the heat shield comprising:
a forward portion;
an aft portion having a flange that extends away from the aft portion, wherein the flange forms an air dam that directs cooling airflow towards the forward portion of the heat shield; and
a second air dam located at least partially surrounding a strut-receiving hole for directing the cooling airflow forward, wherein the second air dam includes a first portion located aft of the strut-receiving hole.

12. The heat shield of claim 11 , wherein the heat shield includes a plurality of metering holes that direct a desired amount of cooling airflow aftward of the heat shield.

13. The heat shield of claim 12 , wherein the plurality of metering holes are of equal size.

14. The heat shield of claim 12 , wherein the plurality of metering holes include metering holes of at least two different sizes.

15. The heat shield of claim 12 , wherein the plurality of metering holes are equally spaced circumferentially around the heat shield.

16. The heat shield of claim 11 , wherein the second air dam includes a second portion and a third portion located on either side of the strut-receiving hole and formed integral with the first portion to direct the cooling airflow forward.

17. The heat shield of claim 16 , further including a third air dam located forward of the strut-receiving hole, but not adjacent to the second and third portions to provide a passageway for directing cooling airflow forward.

Assignees

• United Technologies Corp

Inventors

• Yeager William
• Chuong Conway
• Budnick Matthew

Classifications

• F01D9/065

  Fluid supply or removal conduits traversing the working fluid flow, e.g. for lubrication-, cooling-, or sealing fluids (see also F01D25/16, F01D25/24 and F01D25/26) · CPC title

• F01D25/162

  Bearing supports · CPC title

• Y02T50/675

  Cross-Sectional Technologies · mapped topic

• F02C7/18

  the medium being gaseous, e.g. air {(F02C7/125 takes precedence)} · CPC title

• F01D9/041

  using blades (F01D5/148 takes precedence) · CPC title