# US 2025/0154901 A1 · Open rotor nose cone ram air heat exchanger with exhaust of cooling air through static structure > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0154901 A1 - Document ID: US20250154901A1 - Status: Published application - Kind: A1 - Application number: 18/934,682 - Filed: 2024-11-01 - Published: 2025-05-15 - Earliest claimed: 2023-11-09 - Assignees: Rtx Corporation - Applicants: RTX Corporation - Inventors: William K. Ackermann - Web page: https://patentgrep.com/patent/US20250154901A1 ## CPC - F02C 7/18: the medium being gaseous, e.g. air {(F02C7/125 takes precedence)} - B64C 11/14: Spinners - B64C 11/18: Aerodynamic features - B64C 11/24: Hollow blades - B64C 21/00: Influencing air flow over aircraft surfaces by affecting boundary layer flow - B64D 33/02: of combustion air intakes - B64D 33/08: of power plant cooling systems - F01D 9/065: {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)} - F01D 17/141: {by means of shiftable members or valves obturating part of the flow path} - F01D 25/12: Cooling - F01D 25/125: {of bearings} - F02C 7/042: having variable geometry - F02C 7/057: Control or regulation (conjointly with fuel supply control F02C9/50, with nozzle area control F02K1/16) - F02C 7/125: {by partial arc admission of the working fluid or by intermittent admission of working and cooling fluid} - F02C 7/14: of fluids in the plant {, e.g. lubricant or fuel (F02C7/185 takes precedence)} - F02K 3/025: {the by-pass flow being at least partly used to create an independent thrust component} - F02K 3/075: controlling flow ratio between flows - F02K 3/115: by means of indirect heat exchange - F05D 2250/323: convergent - F05D 2250/324: divergent - F05D 2250/51: Inlet - F05D 2260/213: by the provision of a heat exchanger within the cooling circuit - F05D 2270/17: to control boundary layer - 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) - B64C: AEROPLANES; HELICOPTERS - B64D: EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT - 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 an open rotor configured to rotate with a nose cone. A heat exchanger is positioned within the nose cone and a system for using a working fluid. An inlet from the system is connected to the heat exchanger and an outlet from the heat exchanger connected back to the system. A central opening is in a central portion of the nose cone to deliver cooling air across the heat exchanger, and a duct downstream of the heat exchanger to direct the cooling air radially to at least one static opening such that the cooling air can move radially outwardly through static structure and be directed into a propulsion airflow path. A method and a heat exchange system are also disclosed. ## Claims ### Claim 1 A gas turbine engine comprising: an open rotor configured to rotate with a nose cone; a heat exchanger positioned within the nose cone and a system for using a working fluid, an inlet from the system connected to the heat exchanger and an outlet from the heat exchanger connected back to the system; and a central opening in a central portion of the nose cone to deliver cooling air across the heat exchanger, and a duct downstream of the heat exchanger to direct the cooling air radially to at least one static opening such that the cooling air can move radially outwardly through static structure and be directed into a propulsion airflow path. ### Claim 2 (depends on 1) The gas turbine engine as set forth in claim 1, wherein the open rotor is driven by a gear reduction such that it rotates at a slower speed than a propulsor drive turbine of the gas turbine engine. ### Claim 3 (depends on 1) The gas turbine engine as set forth in claim 1, wherein the central opening in the nose cone directs air into a diffuser. ### Claim 4 (depends on 1) The gas turbine engine as set forth in claim 1, further comprising an exit manifold downstream of the heat exchanger. ### Claim 5 (depends on 4) The gas turbine engine as set forth in claim 4, wherein downstream of the exit manifold the cooling air is connected into a connecting duct which turns it in a radially outward direction. ### Claim 6 (depends on 1) The gas turbine engine as set forth in claim 1, wherein a swirl recovery vane is positioned downstream of the open rotor on an outer housing enclosing a core engine including a propulsor drive turbine of the gas turbine engine. ### Claim 7 (depends on 6) The gas turbine engine as set forth in claim 6, wherein the at least one static opening is in the swirl recovery vane. ### Claim 8 (depends on 7) The gas turbine engine as set forth in claim 7, wherein the at least one static opening comprises a plurality static openings in the swirl recovery vane. ### Claim 9 (depends on 8) The gas turbine engine as set forth in claim 8, wherein at least one of the plurality of static opening is located at a radially outer end of the swirl recovery vane. ### Claim 10 (depends on 1) The gas turbine engine as set forth in claim 1, further comprising: a compressor section; and a turbine section; wherein the outer housing surrounds the compressor section and the turbine section and the at least one static opening is located in the outer housing. ### Claim 11 (depends on 10) The gas turbine engine as set forth in claim 10, wherein the at least one static opening is downstream of the open rotor. ### Claim 12 (depends on 10) The gas turbine engine as set forth in claim 10, wherein the cooling air is connected through static struts radially inward of the outer housing. ### Claim 13 (depends on 1) The gas turbine engine as set forth in claim 1, further comprising a door operable to selectively block airflow into the central opening in a closed position, or allow airflow into the central opening in an open position. ### Claim 14 (depends on 13) The gas turbine engine as set forth in claim 13, wherein an actuator drives the door between the open and closed positions. ### Claim 15 (depends on 1) The gas turbine engine as set forth in claim 1, wherein the heat exchanger is at least one of: rectangular; circular; arc-shaped; or cylindrical. ### Claim 16 (depends on 1) The gas turbine engine as set forth in claim 1, wherein the heat exchanger is cylindrical and includes a central channel through which ambient air is received and passed through the heat exchanger. ### Claim 17 (depends on 1) The gas turbine engine as set forth in claim 1, wherein the heat exchanger is cylindrical and has an outer wall that surrounds an inner cylinder, with a flow channel defined between the inner cylinder and the outer wall. ### Claim 18 A method of operating a gas turbine engine comprising the steps of: 1. driving a gas turbine engine to rotate a nose cone, the nose cone having a central opening; 2. passing a working fluid through a heat exchanger received in the nose cone; 3. passing air into the central opening and across the heat exchanger to cool the working fluid; and 4. passing the air downstream of the heat exchanger outwardly through static structure on the gas turbine engine. ### Claim 19 A heat exchange system for an open rotor gas turbine engine, the heat exchange system comprising: a heat exchanger positioned within a nose cone of the open rotor gas turbine engine and a use for using a working fluid, an inlet from the use connected to the heat exchanger and an outlet from the heat exchanger connected back to the use; and a central opening in a central portion of the nose cone to deliver cooling air across the heat exchanger, and a duct downstream of the heat exchanger to direct the cooling air radially to at least one static opening in a static structure such that the cooling air can move radially outwardly through the at least one static opening static structure and be directed into a propulsion airflow path. ### Claim 20 (depends on 19) The heat exchange system of claim 19 wherein the at least one static opening is in a swirl recovery vane of the open rotor gas turbine engine or in an outer housing that surrounds a compressor, a combustor, and a turbine of the open rotor gas turbine engine.