# US 11,905,884 B1 · Hydrogen fuel system for a gas turbine engine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,905,884 B1 - Document ID: US11905884B1 - Status: Granted - Kind: B1 - Application number: 17/946,708 - Filed: 2022-09-16 - Granted: 2024-02-20 - Earliest claimed: 2022-09-16 - Assignees: General Electric Company - Applicants: General Electric Company - Inventors: Mustafa Dindar; Scott Alan Schimmels - Web page: https://patentgrep.com/patent/US11905884B1 ## CPC - F02C 7/224: Heating fuel before feeding to the burner - F02C 3/22: the fuel or oxidant being gaseous at standard temperature and pressure (F02C3/28 takes precedence) - F02C 7/14: of fluids in the plant {, e.g. lubricant or fuel (F02C7/185 takes precedence)} - F02C 9/40: specially adapted to the use of a special fuel or a plurality of fuels - F02K 1/822: {Heat insulating structures or liners, cooling arrangements, e.g. post combustion liners; Infrared radiation suppressors} - F05D 2260/213: by the provision of a heat exchanger within the cooling circuit - F05D 2260/2214: by increasing the heat transfer surface - F05D 2260/231: Preventing heat transfer - F05D 2260/232: characterized by the cooling medium - 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) - 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 ## Abstract A gas turbine engine includes: a turbomachine including a combustion section and an exhaust assembly arranged in serial flow order; and a fuel system. The fuel system includes: a hydrogen fuel tank for holding a hydrogen fuel in a liquid phase; and a hydrogen delivery assembly in thermal communication with the exhaust assembly. The hydrogen delivery assembly includes: a liquid hydrogen line in fluid communication with the hydrogen fuel tank; a gaseous hydrogen line in fluid communication with the combustion section of the gas turbine engine; and a heat exchanger tubing positioned within the exhaust assembly downstream of the liquid hydrogen line and upstream of the gaseous hydrogen line. ## Claims ### Claim 1 A gas turbine engine comprising: a turbomachine comprising a combustion section and an exhaust assembly arranged in serial flow order, wherein the exhaust assembly comprises a tail cone and a core nozzle circumferentially surrounding at least a portion of the tail cone, wherein the core nozzle comprises a plurality of lobes, the plurality of lobes positioned circumferentially within the exhaust assembly; and a fuel system comprising: a hydrogen fuel tank for holding a hydrogen fuel in a liquid phase; and a hydrogen delivery assembly in thermal communication with the exhaust assembly, the hydrogen delivery assembly comprising: a liquid hydrogen line in fluid communication with the hydrogen fuel tank; a gaseous hydrogen line in fluid communication with the combustion section of the gas turbine engine; and a heat exchanger tubing positioned within the exhaust assembly downstream of the liquid hydrogen line and upstream of the gaseous hydrogen line, wherein the heat exchanger tubing is a plurality of heat exchanger tubing, and wherein the plurality of heat exchanger tubing is positioned in the plurality of lobes, are formed integrally with the plurality of lobes, or both. ### Claim 2 (depends on 1) The gas turbine engine of claim 1, wherein the plurality of lobes defines an inner surface and an outer surface, wherein the plurality of heat exchanger tubing is positioned between the inner surface and the outer surface. ### Claim 3 (depends on 2) The gas turbine engine of claim 2, wherein the core nozzle defines a hot gas flow path with the tail cone, wherein the exhaust assembly comprises a nacelle defining a bypass airflow passage, wherein the inner surface is in thermal communication with the hot gas flow path, wherein the outer surface is in thermal communication with the bypass airflow passage. ### Claim 4 (depends on 3) The gas turbine engine of claim 3, wherein the inner surface is configured to transfer heat from the hot gas flow path to the heat exchanger tubing, wherein the core nozzle comprises a thermal insulation between the heat exchanger tubing and the outer surface. ### Claim 5 (depends on 1) The gas turbine engine of claim 1, wherein the plurality of lobes comprises a first wall and a second wall, and wherein the plurality of heat exchanger tubing extends circumferentially around the first wall and the second wall, is positioned on or integrated into the first wall, is positioned on or integrated into the second wall, or a combination thereof. ### Claim 6 (depends on 1) The gas turbine engine of claim 1, wherein the fuel system further comprises: an auxiliary hydrogen fuel tank for holding an auxiliary hydrogen fuel in a gaseous phase. ### Claim 7 (depends on 1) The gas turbine engine of claim 1, wherein the exhaust assembly is configured to provide heat to the hydrogen delivery assembly to change a phase of the hydrogen fuel. ### Claim 8 (depends on 7) The gas turbine engine of claim 7, wherein the heat exchanger tubing defines a liquid portion and a gaseous portion and wherein, during operation of the fuel system, the hydrogen fuel is in the liquid phase in the liquid portion and in a gaseous phase in the gaseous portion. ### Claim 9 (depends on 1) The gas turbine engine of claim 1, wherein the exhaust assembly comprises a strut, wherein the liquid hydrogen line extends from the hydrogen fuel tank to the heat exchanger tubing through the strut, and wherein the gaseous hydrogen line extends from the heat exchanger tubing to the combustion section through the strut. ### Claim 10 A fuel system for a gas turbine engine, the gas turbine engine comprising a combustion section and an exhaust assembly, the fuel system comprising: a hydrogen fuel tank for holding a hydrogen fuel in a liquid phase; and a hydrogen delivery assembly in thermal communication with the exhaust assembly, the hydrogen delivery assembly comprising: a liquid hydrogen line in fluid communication with the hydrogen fuel tank; a gaseous hydrogen line in fluid communication with the combustion section of the gas turbine engine; and a heat exchanger tubing positioned within the exhaust assembly downstream of the liquid hydrogen line and upstream of the gaseous hydrogen line, wherein the exhaust assembly comprises a tail cone and a core nozzle circumferentially surrounding at least a portion of the tail cone, wherein the core nozzle comprises a plurality of lobes, the plurality of lobes positioned circumferentially within the exhaust assembly, wherein the heat exchanger tubing is a plurality of heat exchanger tubing, and wherein the plurality of heat exchanger tubing is positioned in the plurality of lobes, are formed integrally with the plurality of lobes, or both. ### Claim 11 (depends on 10) The fuel system of claim 10, wherein the plurality of lobes defines an inner surface and an outer surface, wherein the plurality of heat exchanger tubing is positioned between the inner surface and the outer surface. ### Claim 12 (depends on 11) The fuel system of claim 11, wherein the core nozzle defines a hot gas flow path with the tail cone, wherein the exhaust assembly comprises a nacelle defining a bypass airflow passage, wherein the inner surface is in thermal communication with the hot gas flow path, wherein the outer surface is in thermal communication with the bypass airflow passage. ### Claim 13 (depends on 12) The fuel system of claim 12, wherein the inner surface is configured to transfer heat from the hot gas flow path to the heat exchanger tubing, wherein the core nozzle comprises a thermal insulation between the heat exchanger tubing and the outer surface. ### Claim 14 (depends on 10) The fuel system of claim 10, wherein the plurality of lobes comprises a first wall and a second wall, and wherein the plurality of heat exchanger tubing extends circumferentially around the first wall and the second wall, is positioned on or integrated into the first wall, is positioned on or integrated into the second wall, or a combination thereof. ### Claim 15 (depends on 10) The fuel system of claim 10, wherein the fuel system further comprises: an auxiliary hydrogen fuel tank for holding an auxiliary hydrogen fuel in a gaseous phase. ### Claim 16 (depends on 10) The fuel system of claim 10, wherein the exhaust assembly is configured to provide heat to the hydrogen delivery assembly to change a phase of the hydrogen fuel. ### Claim 17 (depends on 16) The fuel system of claim 16, wherein the heat exchanger tubing defines a liquid portion and a gaseous portion and wherein, during operation of the fuel system, the hydrogen fuel is in the liquid phase in the liquid portion and in a gaseous phase in the gaseous portion. ### Claim 18 (depends on 10) The fuel system of claim 10, wherein the exhaust assembly comprises a strut, wherein the liquid hydrogen line extends from the hydrogen fuel tank to the heat exchanger tubing through the strut, and wherein the gaseous hydrogen line extends from the heat exchanger tubing to the combustion section through the strut.