# US 2021/0340911 A1 · Thermal management of a gas turbine engine shaft > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0340911 A1 - Document ID: US20210340911A1 - Status: Published application - Kind: A1 - Application number: 17/376,482 - Filed: 2021-07-15 - Published: 2021-11-04 - Earliest claimed: 2018-05-31 - Assignees: Raytheon Technologies Corporation - Applicants: Raytheon Technologies Corporation - Inventors: Gary D. Roberge; Jorn Axel Glahn - Web page: https://patentgrep.com/patent/US20210340911A1 ## CPC - F02C 6/06: providing compressed gas (F02C6/10 takes precedence) - F02C 7/18: the medium being gaseous, e.g. air {(F02C7/125 takes precedence)} - F01D 5/085: {cooling fluid circulating inside the rotor} - F01D 25/125: {of bearings} - F02C 7/32: Arrangement, mounting, or driving, of auxiliaries - F02K 3/06: with front fan - F05D 2240/50: Bearings - F05D 2240/55: Seals - F05D 2240/61: Hollow - F05D 2260/20: Heat transfer, e.g. cooling - Y02T 50/60: Efficient propulsion technologies, e.g. for aircraft - F02C: GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS (construction of turbines F01D; jet-propulsion plants F02K; construction of compressors or fans F04; generating combustion products of high pressure or high velocity F23R; using gas turbines in compression refrigeration plants F25B11/00) - F01D: NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES (machines or engines for liquids F03; non-positive displacement pumps F04D) - F02K: JET-PROPULSION PLANTS (features of jet-propulsion plants common to gas-turbine plants, air intakes or fuel supply control of air-breathing jet-propulsion plants F02C7/00, F02C9/00) - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A gas turbine engine includes a fan rotor, a compressor section, a combustor section, and a turbine section. The turbine section is positioned downstream of the combustor section. A fan drive turbine in the turbine section, and a shaft connects the fan drive turbine to the fan rotor. An inlet duct is connected to a cooling air source and connected to a cooling compressor downstream of the fan drive turbine. The cooling compressor is connected to an air source, and connected to a turning duct for passing compressed air in an upstream direction through the shaft. A method is also disclosed. ## Claims ### Claim 1 A gas turbine engine comprising: a fan rotor, a compressor section, a combustor section, and a turbine section, said turbine section being positioned downstream of said combustor section; a fan drive turbine in said turbine section, and a shaft connecting said fan drive turbine to said fan rotor; an inlet duct connected to a cooling air source and connected to a cooling compressor downstream of said fan drive turbine, and said cooling compressor connected to an air source, and connected to a turning duct for passing compressed air in an upstream direction through said shaft; and wherein said cooling compressor is supported by a bearing which also supports said shaft. ### Claim 2 (depends on 1) The gas turbine engine as set forth in claim 1, wherein there being connection passages in said shaft communicating inner and outer passages in said shaft such that the air, having passed in said upstream location in one of said inner and outer passages is returned in the other of said inner and outer passages in a downstream direction to provide cooling to said shaft. ### Claim 3 (depends on 2) The gas turbine engine as set forth in claim 2, wherein said turning duct extending to initially pass air downstream of said cooling compressor in a downstream direction, and then turn the air into the upstream direction. ### Claim 4 (depends on 3) The gas turbine engine as set forth in claim 3, wherein a tube is positioned within said shaft to define said inner and outer passages, and said connection passages extending through said tube to communicate between said inner and outer passages. ### Claim 5 (depends on 4) The gas turbine engine as set forth in claim 4, wherein a plurality of bearings support said shaft. ### Claim 6 (depends on 5) The gas turbine engine as set forth in claim 5, wherein bearing outlet passages extend through said shaft, said bearing outlet passages positioned to provide cooling air to said bearings. ### Claim 7 (depends on 1) The gas turbine engine as set forth in claim 1, wherein said inlet duct communicates with a bypass duct that is positioned outwardly of a core engine including said compressor section, said combustor section, and said turbine section, and said bypass duct providing said source of air. ### Claim 8 (depends on 1) The gas turbine engine as set forth in claim 1, wherein said cooling compressor is connected to said shaft to a flexible connection. ### Claim 9 (depends on 1) The gas turbine engine as set forth in claim 1, wherein a first seal seals against a downstream end of said shaft. ### Claim 10 (depends on 1) The gas turbine engine as set forth in claim 1, wherein a gear reduction is positioned between said fan drive turbine and said fan rotor. ### Claim 11 (depends on 10) The gas turbine engine as set forth in claim 10, wherein a plurality of bearings support said shaft. ### Claim 12 (depends on 11) The gas turbine engine as set forth in claim 11, wherein bearing outlet passages extend through said shaft, said bearing outlet passages positioned to provide cooling air to said bearings. ### Claim 13 A gas turbine engine comprising: a fan rotor, a compressor section, a combustor section, and a turbine section, said turbine section being positioned downstream of said combustor section; a fan drive turbine in said turbine section, and a shaft connecting said fan drive turbine to said fan rotor; an inlet duct connected to a cooling air source and connected to a cooling compressor downstream of said fan drive turbine, and said cooling compressor connected to an air source, and connected to a turning duct for passing compressed air in an upstream direction through said shaft; and wherein said turning duct is positioned relative to a flange at an end of said shaft with an intermediate seal to provide a sealed connection between said duct and said shaft. ### Claim 14 (depends on 13) The gas turbine engine as set forth in claim 13, wherein a plurality of bearings support said shaft. ### Claim 15 (depends on 14) The gas turbine engine as set forth in claim 14, wherein bearing outlet passages extend through said shaft, said bearing outlet passages positioned to provide cooling air to said bearings. ### Claim 16 (depends on 13) The gas turbine engine as set forth in claim 13, wherein there being connection passages in said shaft communicating inner and outer passages in said shaft such that the air, having passed in said upstream location in one of said inner and outer passages is returned in the other of said inner and outer passages in a downstream direction to provide cooling to said shaft. ### Claim 17 (depends on 16) The gas turbine engine as set forth in claim 16, wherein said turning duct extending to initially pass air downstream of said cooling compressor in a downstream direction, and then turn the air into the upstream direction. ### Claim 18 (depends on 17) The gas turbine engine as set forth in claim 17, wherein a tube is positioned within said shaft to define said inner and outer passages, and said connection passages extending through said tube to communicate between said inner and outer passages. ### Claim 19 (depends on 13) The gas turbine engine as set forth in claim 13, wherein a plurality of bearings support said shaft. ### Claim 20 (depends on 19) The gas turbine engine as set forth in claim 19, wherein bearing outlet passages extend through said shaft, said bearing outlet passages positioned to provide cooling air to said bearings.