Abstract: A method of managing thermal energy in a propulsion system includes diverting a flow of bleed air from a compressor section of the propulsion system. An amount of the flow of bleed air diverted from the compressor section is at least 5% of an inlet flow at an inlet of a high pressure compressor of the compressor section. The flow of bleed air is provided to a thermal management system. The flow of bleed air is passed through an expansion turbine of the thermal management system. The flow of bleed air is provided to a thermal load.

Abstract: The present disclosure is directed to a gas turbine engine defining a radial direction, a longitudinal direction, and a circumferential direction, an upstream end and a downstream end along the longitudinal direction, and an axial centerline extended along the longitudinal direction. The gas turbine engine includes a fan assembly including a plurality of fan blades rotatably coupled to a fan rotor in which the fan blades define a maximum fan diameter and a fan pressure ratio. The gas turbine engine further includes a low pressure (LP) turbine defining a core flowpath therethrough generally along the longitudinal direction. The core flowpath defines a maximum outer flowpath diameter relative to the axial centerline. The gas turbine engine defines a fan to turbine diameter ratio of the maximum fan diameter to the maximum outer flowpath diameter. The fan to turbine diameter ratio over the fan pressure ratio is approximately 0.90 or greater.

Abstract: A fuel system is provided for an aircraft having a fuel source. The fuel system includes a fuel oxygen reduction unit defining a liquid fuel supply path, a stripping gas supply path, a liquid fuel outlet path, and a stripping gas return path, wherein the stripping gas return path is in airflow communication with the fuel source.

Abstract: A structure for damping at a fluid manifold assembly for an engine is generally provided. The fluid manifold assembly includes a first walled conduit defining a first fluid passage therewithin. A flow of fluid defining a first frequency is permitted through the first fluid passage. A second walled conduit includes a pair of first portions each coupled to the first walled conduit. A second portion is coupled to the pair of first portions. A second fluid passage is defined through the first portion and the second portion in fluid communication with the first fluid passage. The flow of fluid is permitted through the second fluid passage at a second frequency approximately 180 degrees out of phase from the first frequency.

Abstract: A thermal management system includes a first heat source assembly including a first heat source exchanger, a first thermal fluid inlet line extending to the first heat source exchanger, and a first thermal fluid outlet line extending from the first heat source exchanger; a second heat source assembly including a second heat source exchanger, a second thermal fluid inlet line extending to the second heat source exchanger, and second a thermal fluid outlet line extending from the second heat source exchanger; a shared assembly including a thermal fluid line and a heat sink exchanger, the shared assembly defining an upstream junction in fluid communication with the first thermal fluid outlet line and second thermal fluid outlet line and a downstream junction in fluid communication with the first thermal fluid inlet line and second thermal fluid inlet line; and a controller configured to selectively fluidly connect the first heat source assembly or the second heat source assembly to the shared assembly.

Abstract: A gas turbine engine may include a fan, a plurality of inlet pre-swirl features disposed upstream of a fan, and an outlet guide vane assembly disposed downstream of the fan. The outlet guide vane assembly includes a plurality of outlet guide vanes that may define an outlet guide vane solidity profile, wherein the outlet guide vane solidity profile is achieves a minimum solidity at a radial position between an inner boundary and seventy percent of an outlet guide vane span. The fan includes a plurality of fan blades that may define a fan solidity profile, wherein the fan solidity profile maintains a solidity of greater than 1.1 between a radial position at seventy percent of the fan blade span and an outer boundary.

Abstract: A system and method for using a fuel with an engine, an airframe having an aircraft heat load, a fuel tank, and a fuel oxygen reduction unit are provided. The method includes receiving an inlet fuel flow in the fuel oxygen reduction unit for reducing an amount of oxygen in the inlet fuel flow; separating a fuel/gas mixture within the fuel oxygen reduction unit into an outlet gas flow and an outlet fuel flow exiting the fuel oxygen reduction unit; controlling a first portion of the outlet fuel flow to the engine; and controlling a second portion of the outlet fuel flow to the airframe to transfer heat between the second portion of the outlet fuel flow and the aircraft heat load.

Abstract: An un-ducted turbofan engine defining a radial direction and an axial direction that includes a core engine, a fan, a plurality of variable outlet guide vanes, and a pitch change mechanism. Each of the plurality of variable outlet guide vanes are attached in a rotatable manner to the core engine of the un-ducted turbofan engine. The pitch change mechanism is positioned radially between the engine air flowpath and the plurality of variable outlet guide vanes and coupled to at least one variable outlet guide vane of the plurality of variable outlet guide vanes for changing a pitch of the at least one variable outlet guide vane.

Abstract: A thermal management system for transferring heat between fluids includes a thermal transport bus through which a heat exchange fluid flows. Additionally, the system includes a heat source heat exchanger arranged along the bus such that heat is added to the fluid flowing through the heat source heat exchanger. Moreover, the system includes a plurality of heat sink heat exchangers arranged along the bus such that heat is removed from the fluid flowing through the plurality of heat sink heat exchangers. Furthermore, the system includes a bypass conduit fluidly coupled to the bus such that the bypass conduit allows the fluid to bypass one of the heat source heat exchanger or one of the heat sink heat exchangers. In addition, the system includes a valve configured to control a flow of the fluid through the bypass conduit based on a pressure of the fluid within the bus.

Abstract: Systems and methods for adjusting airflow distortion in a gas turbine engine using a translating inlet assembly are provided. In one embodiment, a core engine of a gas turbine engine can include a compressor section, a combustion section, and a turbine section in series flow and defining at least in part an engine airflow path. The compressor section can include an inner flowpath surface. A core casing can enclose the core engine. A forward end of the core casing can include a translating inlet assembly moveable between a first position and a second position. The translating inlet assembly and the inner flowpath surface can together define an inlet to an engine airflow path. A translating inlet assembly can define a first inlet area in the first position and a second inlet area in the second position, the first inlet area being greater than the second inlet area.

Abstract: A method of operating a fuel oxygen reduction unit for a vehicle or a gas turbine engine of the vehicle is provided. The fuel oxygen reduction unit including a contactor and a fuel gas separator, and further defining a stripping gas flowpath in flow communication with a stripping gas inlet of the contactor and a stripping gas outlet of the fuel gas separator. The method includes receiving data indicative of a parameter of a stripping gas flow through the stripping gas flowpath or of a component in flow communication with the stripping gas flow through the stripping gas flowpath; and determining an operability condition of the fuel oxygen reduction unit, or a component operable with the fuel oxygen reduction unit, based on the data received indicative of the parameter of the stripping gas flow or of the component in flow communication with the stripping gas flow.

Abstract: A gas turbine engine includes a compressor section and a turbine section together defining a core air flowpath. Additionally, a rotary component is rotatable with at least a portion of the compressor section and at least a portion of the turbine section. An electric machine is mounted coaxially with the rotary component and positioned at least partially inward of the core air flowpath along a radial direction of the gas turbine engine. A cavity wall defines at least in part a buffer cavity surrounding at least a portion of the electric machine to thermally insulate the electric machine, e.g., from the relatively high temperatures within the core air flowpath.

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 fuel system is provided for an aircraft having a fuel source. The fuel system includes a fuel oxygen reduction unit defining a liquid fuel supply path, a stripping gas supply path, a liquid fuel outlet path, and a stripping gas return path, wherein the stripping gas return path is in airflow communication with the fuel source.

Abstract: The present disclosure is directed to a gas turbine engine defining a radial direction, a longitudinal direction, and a circumferential direction, an upstream end and a downstream end along the longitudinal direction, and an axial centerline extended along the longitudinal direction. The gas turbine engine includes a fan assembly including a plurality of fan blades rotatably coupled to a fan rotor in which the fan blades define a maximum fan diameter and a fan pressure ratio. The gas turbine engine further includes a low pressure (LP) turbine defining a core flowpath therethrough generally along the longitudinal direction. The core flowpath defines a maximum outer flowpath diameter relative to the axial centerline. The gas turbine engine defines a fan to turbine diameter ratio of the maximum fan diameter to the maximum outer flowpath diameter. The fan to turbine diameter ratio over the fan pressure ratio is approximately 0.90 or greater.

Abstract: Propulsion systems and methods of operation are provided. An exemplary propulsion system comprises a rotating element; a stationary element; an inlet duct having an inlet between the rotating and stationary elements, the inlet passing radially inward of the stationary element; a ducted fan disposed in the inlet duct downstream of the inlet and having an axis of rotation and a plurality of blades; a gas turbine engine core having a high pressure compressor, a combustor, and a high pressure turbine in serial relationship; and a booster compressor disposed between the ducted fan and the gas turbine engine core. At least one of the ducted fan and the booster compressor is driven by a variable speed power source such that the rotational speed of the ducted fan and/or booster compressor is controllable independently from the rotational speed of any rotor of the propulsion system.

Abstract: A method for energy conversion for a vehicle is provided. The method including extracting a flow of compressed fluid from a compressor section of a propulsion system; flowing the flow of compressed fluid to a turbine operably coupled to a driveshaft, in which the driveshaft is operably coupled to a load device; expanding the flow of compressed fluid through the turbine to generate an output torque at the driveshaft to operate the load device; and flowing the expanded flow of compressed fluid from the turbine to thermal communication with a thermal load.

Abstract: An aeronautical propulsion device including a fan and a plurality of variable guide vanes is provided. The fan includes a plurality of fan blades for providing a flow of air and the plurality of variable guide vanes are configured for directing air to or from the fan in a desired direction. Each of the plurality of guide vanes defines an inner end along the radial direction and is attached to a housing of the portion device at the inner end in a rotatable manner. The propulsion device further includes a pitch change mechanism positioned in the housing and mechanically coupled to at least one of the plurality of guide vanes for changing a pitch of the at least one of the plurality of guide vanes.

Abstract: A turbine engine includes a compressor section, a combustion section, a turbine section, and an exhaust section in serial flow order and together defining a core air flowpath; a fuel delivery system for providing a flow of fuel to the combustion section; and a waste heat recovery system. The waste heat recovery system includes a heat source exchanger in thermal communication with the turbine section, the exhaust section, or both; a heat sink exchanger in thermal communication with the fuel delivery system, the core air flowpath, or both; a thermal transfer bus including a thermal transfer fluid and extending from the heat source exchanger to the heat sink exchanger; and a pump in fluid communication with the thermal transfer bus downstream of the heat source exchanger and upstream of the heat sink exchanger for increasing a temperature and a pressure of the thermal transfer fluid in the thermal transfer bus.

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.