초록

A turbine exhaust case has an outer housing to be secured within a gas turbine engine and a central hub. Struts extend between the outer housing and the central hub. The struts are formed at least in part of a first material. The central hub is formed at least in part of a second material.

대표청구항 ▼

1. A turbine exhaust case for use in a gas turbine engine comprising: an outer housing to be secured within the gas turbine engine;a central hub, the central hub including a support surface for supporting a shaft of a turbine;struts extending between the outer housing and the central hub;the struts

1. A turbine exhaust case for use in a gas turbine engine comprising: an outer housing to be secured within the gas turbine engine;a central hub, the central hub including a support surface for supporting a shaft of a turbine;struts extending between the outer housing and the central hub;the struts formed at least in part of a first material and the central hub formed at least in part of a second material, wherein the first material having better resistance to high temperatures and to maintaining metallurgical properties at high temperatures than does the second material; andwherein a radially outer portion of the airfoil is secured to a strut plate in the outer housing, and the strut plates are secured to the radially outer location on the struts, the strut plates formed of the first material. 2. The turbine exhaust case as set forth in claim 1, wherein the central hub is one of a cast, forged or wrought part. 3. The turbine exhaust case as set forth in claim 2, wherein the central hub has a plurality of radially outwardly extending stubs and the struts are welded to the stubs, such that radially inner portions of an airfoil are formed by the stubs of the second material, and radially outward portions are formed by the struts and the first material. 4. The turbine exhaust case as set forth in claim 3, wherein circumferentially intermediate plates are positioned between the strut plates, with the circumferentially intermediate plates not being secured to the struts and the circumferentially intermediate plates formed of the second material. 5. The turbine exhaust case as set forth in claim 3, wherein a shroud mount is formed as part of the outer housing and is attached to a plurality of the struts, with the shroud mount formed of the first material. 6. The turbine exhaust case as set forth in claim 3, wherein a radially outermost stub is formed extending radially inwardly from the strut plate and is secured to the strut. 7. The turbine exhaust case as set forth in claim 1, wherein the struts are formed of sheet metal of the first material. 8. The turbine exhaust case as set forth in claim 1, wherein the inner hub includes a radially innermost conical ring, a radially outer cylindrical ring, and a plurality of ribs extending between the radially inner and outer cylindrical ring to form the inner hub. 9. A gas turbine engine comprising: a turbine section including at least a turbine rotor, with the turbine rotor including a shaft supported, in part, in a turbine exhaust case, and the turbine exhaust case including an outer housing secured within the gas turbine engine;the turbine exhaust case having a central hub, the central hub including a support surface for supporting the shaft;struts extending between the outer housing and the central bore, the struts formed at least in part of a first material and the central hub formed at least in part of a second material, wherein the first material having better resistance to high temperatures and to maintaining metallurgical properties at high temperatures than does the second material; andwherein a radially outer portion of the airfoil is secured to a strut plate in the outer housing, and the strut plates are secured to a radially outer location on the struts, the strut plates formed of the first material. 10. The gas turbine engine as set forth in claim 9, wherein the central hub is one of a cast, forged or wrought part. 11. The gas turbine engine as set forth in claim 10, wherein the struts are formed of sheet metal of the first material. 12. The gas turbine engine as set forth in claim 11, wherein the central hub has a plurality of radially outwardly extending stubs and the struts are welded to the stubs, such that radially inner portions of an airfoil are formed by the stubs of the second material, and radially outward portions are formed by the struts and the first material. 13. The gas turbine engine as set forth in claim 12, wherein circumferentially intermediate plates are positioned between the strut plates, with the circumferentially intermediate plates not being secured to the struts and the circumferentially intermediate plates formed of the second material. 14. The gas turbine engine as set forth in claim 12, wherein a shroud mount is formed as part of the outer housing and is attached to a plurality of the struts, with the shroud mount formed of the first material. 15. The gas turbine engine as set forth in claim 12, wherein a radially outermost stub is formed extending radially inwardly from the strut plate and is secured to the strut. 16. The gas turbine engine as set forth in claim 9, wherein the inner hub includes a radially innermost ring, a radially outer ring, and a plurality of ribs extending between the radially inner and outer rings to form the inner hub. 17. The gas turbine engine as set forth in claim 16, wherein the radially innermost conical ring extends to be a flange, and a pair of bearing support flanges are mounted at a location that is aft of the flange, with each of the bearing support flanges supporting a bearing supporting the shaft. 18. The gas turbine engine as set forth in claim 9, wherein the turbine rotor driving a fan rotor through a gear reduction. 19. The gas turbine engine as set forth in claim 18, wherein the turbine exhaust case operating at temperatures in excess of about 1200° F. 20. The gas turbine engine as set forth in claim 18, wherein the turbine exhaust case operating at core bleed levels of greater than 15% at low flow conditions, including ground idle.