Abstract: An aircraft propulsion system and computing system are provided. The propulsion system includes a low pressure (LP) spool and a core engine having a high pressure (HP) spool. A frame is positioned in serial flow arrangement between an HP turbine and an LP turbine. The frame includes an inter-turbine burner including a strut forming an outlet opening into a core flowpath of the propulsion system. A first fuel system is configured to flow a liquid fuel to a combustion section for generating first combustion gases. A second fuel system is configured to flow a gaseous fuel to the core flowpath via the inter-turbine burner for generating second combustion gases. The propulsion system forms a rated power output ratio of the core engine and the inter-turbine burner with the LP spool between 1.5 and 5.7.

Abstract: A shaft power transfer system includes a first mechanical clutch mechanism operably coupling a high-pressure shaft to a low-pressure shaft. The first mechanical clutch mechanism transfers power from the high-pressure shaft to the low-pressure shaft at a predefined first speed transient condition. The system further includes a second mechanical clutch mechanism that operably couples the low-pressure shaft to the high-pressure shaft. The second mechanical clutch mechanism transfers power from the low-pressure shaft to the high-pressure shaft at a predefined second speed transient condition where the predefined first speed transient condition is different than the predefined second speed transient condition.

Abstract: A nozzle assembly for a gas turbine engine and methods for assembling a nozzle assembly are provided. In one example aspect, the nozzle assembly includes an outer wall and an inner wall radially spaced from the outer wall. The outer wall defines a plurality of mounting openings spaced circumferentially from one another. The inner wall defines a plurality of mounting openings spaced circumferentially from one another. The mounting openings defined by the inner wall are positioned circumferentially between adjacent mounting openings defined by the outer wall. The nozzle assembly includes vanes that are inserted through the mounting openings of the outer wall in a radially inward direction and vanes that are inserted through the mounting openings of the inner wall in a radially outward direction in an alternating manner.

Abstract: A gas turbine engine defines a working air flowpath and includes an electrical system having an electric machine coupled to the rotary component at least partially inward of the working air flowpath along the radial direction and an electric bus electrically coupled to the electric machine. The electric bus includes an electric line extending through the working air flowpath within or downstream of a turbine section. The engine further includes a cooling system including a cooling fluid supply line and a cooling fluid return line, wherein a portion of the electric line extending though the working air flowpath is substantially embedded within the cooling fluid supply line, and wherein a portion of the cooling fluid supply line extending though the working air flowpath is substantially embedded within the cooling fluid return line.

Abstract: A method is provided of controlling a cooled cooling air system for an aeronautical gas turbine engine. The method includes: receiving data indicative of an ambient condition of the aeronautical gas turbine engine, data indicative of a deterioration parameter of the aeronautical gas turbine engine, data indicative of an operating condition of the aeronautical gas turbine engine, or a combination thereof; and modifying a cooling capacity of the cooled cooling air system in response to the received data indicative of the ambient condition of the aeronautical gas turbine engine, data indicative of the deterioration parameter of the aeronautical gas turbine engine, data indicative of an operating condition of the aeronautical gas turbine engine, or the combination thereof.

Abstract: A system for energy conversion that includes a propulsion system, a fuel circuit, a combustion device, a turbine, and a load device. The fuel circuit is in fluid communication with a fuel tank and a fuel flow control device that separates a flow of fuel into a first portion and a second portion. The combustion device receives a flow of oxidizer and the second portion of fuel to generate combustion gases. The turbine receives the combustion gases from the combustion device via a fluid circuit. The load device is operably coupled to the turbine via a driveshaft and is configured to receive torque from the driveshaft.

Abstract: A method is provided for operating a thermal management system of a gas turbine engine. The method includes: operating the gas turbine engine to start-up the gas turbine engine; receiving data indicative of a state of a thermal transport bus of the thermal management system using a sensor, the state of the thermal transport bus including a phase of a thermal fluid within the thermal transport bus; and starting a pump of a pump assembly in response to receiving data indicative of the state of the thermal transport bus of the thermal management system, the pump in fluid communication with the thermal transport bus.

Abstract: A vehicle is provided including a structure including a skin defining an outside surface exposed to ambient cooling flow and an inside surface. The structure includes a first structural member extending from the inside surface of the skin and a second structural member extending from the inside surface of the skin; and a thermal management system including a heat exchanger assembly positioned adjacent to, and in thermal communication with, the inside surface of the skin, the heat exchanger assembly positioned at least partially between the first and second structural members of the structure.

Abstract: A system for controlling blade clearances within a gas turbine engine includes a rotor disk and a rotor blade coupled to the rotor disk. Additionally, the system includes an outer turbine component positioned outward of the rotor blade such that a clearance is defined between the rotor blade and the outer turbine component. Furthermore, the system includes a heat exchanger configured to receive a flow of cooling air bled from the gas turbine engine and transfer heat from the received flow of the cooling air to a flow of coolant to generate cooled cooling air. Moreover, the system includes a valve configured to control the flow of the coolant to the heat exchanger. In this respect, the cooled cooling air is supplied to at least one of the rotor disk or the rotor blade to adjust the clearance between the rotor blade and the outer turbine component.

Abstract: A heat engine comprising a compressor providing a flow of compressed air from a core flowpath of the heat engine; a cooled cooling air (CCA) heat exchanger system to which the flow of compressed air is provided from the compressor; a coolant supply system providing a flow of coolant to the CCA heat exchanger in thermal communication with the flow of compressed air at the CCA heat exchanger, in which the coolant supply system and CCA heat exchanger together define a CCA circuit through which the compressed air flows in thermal communication with the coolant; and a hot section disposed downstream of the compressor section along the core flowpath through which combustion gases flow, in which the hot section defines a secondary flowpath through which the flow of compressed air from the CCA heat exchanger is provided.

Abstract: A heat exchanger and heat exchanger core are provided. The heat exchanger core includes a plurality of columnar passages extending between an inlet plenum of the heat exchanger core and an outlet plenum of the heat exchanger core, the columnar passages formed monolithically in a single fabrication process.

Abstract: Heat exchangers, heat exchanger systems, and hypersonic vehicles are provided. For example, a heat exchanger is provided that comprises a first chamber for receipt of a flow of cool fluid and a second chamber for receipt of a flow of hot fluid. The heat exchanger further comprises a buffer fluid flowpath for circulation of a buffer fluid therethrough. The buffer fluid circulates within the buffer fluid flowpath disposed between the first chamber and the second chamber to transfer heat from the hot fluid to the cool fluid. In certain embodiments, a hypersonic vehicle comprises such a heat exchanger, and the cool fluid is cryogenic or near-cryogenic fuel of the hypersonic vehicle and the hot fluid is engine bleed air from a hypersonic propulsion engine of the vehicle.

Abstract: A method of manufacturing a heat exchanger is provided. The method includes forming a first substrate by additively manufacturing a body defining a first outer surface and a second outer surface opposite the first outer surface, a first partial fluid flow channel formed within the first outer surface, a second partial fluid flow channel formed within the second outer surface, and at least one internal fluid flow channel completely formed within the body, and coupling the first substrate to a second substrate including a partial fluid flow channel formed within a surface of the second substrate such that the first partial fluid flow channel of the first substrate and the partial fluid flow channel of the second substrate combine to form a combined fluid flow channel.

Abstract: A gas supply system is provided herein. The gas supply system includes a fuel oxygen reduction unit having a circuit defining a gas flowpath for a flow of a stripping gas. A reservoir is in selective fluid communication with the fuel oxygen reduction unit and is configured to store a portion of the stripping gas from the circuit. The reservoir is further configured to be in selective fluid communication with the fuel system component when installed in a vehicle to provide the stored portion of the stripping gas to the fuel system component in response to detection of a purge condition.

Abstract: A method for thermal management for an aircraft includes extracting a flow of compressed fluid from a compressor section of a propulsion system. The flow of compressed fluid is passed through an anti-ice system. The flow of compressed fluid flows from the anti-ice system to a turbine. The flow of compressed fluid is expanded across the turbine. The expanded flow of compressed fluid then flows to thermal communication with a thermal load.

Abstract: A vehicle is provided including a structure including a skin defining an outside surface exposed to ambient cooling flow and an inside surface. The structure includes a first structural member extending from the inside surface of the skin and a second structural member extending from the inside surface of the skin; and a thermal management system including a heat exchanger assembly positioned adjacent to, and in thermal communication with, the inside surface of the skin, the heat exchanger assembly positioned at least partially between the first and second structural members of the structure.

Abstract: A system for energy conversion that includes a propulsion system, a fuel circuit, a combustion device, a turbine, and a load device. The fuel circuit is in fluid communication with a fuel tank and a fuel flow control device that separates a flow of fuel into a first portion and a second portion. The combustion device receives a flow of oxidizer and the second portion of fuel to generate combustion gases. The turbine receives the combustion gases from the combustion device via a fluid circuit. The load device is operably coupled to the turbine via a driveshaft and is configured to receive torque from the driveshaft.

Abstract: A thermal device includes a plate defining a plurality of convex curves and a plurality of concave curves. Each convex curve is positioned between a pair of adjacent concave curves of the plurality of concave curves. Each concave curve is positioned between a pair of adjacent convex curves of the plurality of convex curves. Each concave curve defines a vertex. The thermal device also includes a plurality of pins. Each pin of the plurality of pins extends from the vertex of a different concave curve of the plurality of concave curves and extends away from the plate.

Abstract: A heat engine comprising a compressor providing a flow of compressed air from a core flowpath of the heat engine; a cooled cooling air (CCA) heat exchanger system to which the flow of compressed air is provided from the compressor; a coolant supply system providing a flow of coolant to the CCA heat exchanger in thermal communication with the flow of compressed air at the CCA heat exchanger, in which the coolant supply system and CCA heat exchanger together define a CCA circuit through which the compressed air flows in thermal communication with the coolant; and a hot section disposed downstream of the compressor section along the core flowpath through which combustion gases flow, in which the hot section defines a secondary flowpath through which the flow of compressed air from the CCA heat exchanger is provided.

Abstract: A method and system for bleed flow power generation is provided. The engine includes a core flowpath formed by a compressor section, a heat addition system, and an expansion section in serial flow arrangement. A bleed circuit is extended from the core flowpath to extract a portion of compressed fluid from the core flowpath. The method and system include bleeding compressed fluid through a bleed circuit extended in fluid communication from the core flowpath of the engine; flowing the compressed fluid through the bleed circuit to a turbine rotor positioned at the bleed circuit; extracting, via the turbine rotor, energy from the flow of compressed fluid across the turbine rotor; and receiving energy at an electric machine operably coupled to the turbine rotor.