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: 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 gas turbine engine may include a turbomachine defining a core flow having a core mass flow rate therethrough during operation. A bleed assembly is provided to include a bleed flow machine and a machine load. The bleed flow machine is provided in fluid communication with the compressor section of the turbomachine and configured to drive the machine load. A machine outlet in fluid communication with the bleed assembly provides a bleed flow therethrough during operation of the gas turbine engine, the bleed flow defining a bleed mass flow rate. A compressor section of the turbomachine is configured to provide the bleed flow through the bleed flow machine and the machine outlet to an aircraft flow assembly, wherein the bleed mass flow rate is at least twelve percent (12%) of the core mass flow rate.

Abstract: A gas turbine engine comprises a turbomachine defining a core flow therethrough during operation. A flow tap is provided in fluid communication with the turbomachine, wherein the flow tap is configured to receive a portion of the core flow therethrough as a bleed flow. A bleed assembly includes a machine load, a bleed flow machine, and a bleed regulator. The bleed flow machine is disposed in fluid communication with the turbomachine through the flow tap, and is configured to drive the machine load. The bleed regulator is configured to regulate a bleed output provided to the bleed flow machine by controlling a capture rate of the bleed flow by the bleed flow machine.

Abstract: A gas turbine engine includes a turbomachine defining a core flow therethrough during operation. A first flow tap is configured to receive a first bleed flow from upstream of the combustion section. A second flow tap is configured to receive a second bleed flow from downstream of the combustion section. A first flow outlet is provided in fluid communication with the first flow tap and a second flow outlet is provided in fluid communication with the second flow tap. The first flow outlet and the second flow outlet are configured to direct the first bleed flow and the second bleed flow to at least one aircraft flow assembly.

Abstract: A gas turbine engine includes a turbomachine, the turbomachine defining a core flow therethrough during operation. A first heat exchange assembly is in fluid communication with the turbomachine for receiving a first bleed flow from the turbomachine. A second heat exchange assembly is in fluid communication with the turbomachine for receiving a second bleed flow from the turbomachine. A first flow outlet is provided for receiving the first bleed flow from the first heat exchange assembly and providing the first bleed flow to a first aircraft flow assembly. A second flow outlet is provided for receiving the second bleed flow and providing the second bleed flow from the second heat exchange assembly to a second aircraft flow assembly.

Abstract: A thermal management system is provided for incorporation into a gas turbine engine, wherein the gas turbine engine, the aircraft, or both define a vertical direction. The thermal management system including: a thermal transport bus having a thermal fluid flowing therethrough; a plurality of heat source exchangers in thermal communication with the thermal fluid in the thermal transport bus; and a pump assembly in flow communication with the thermal transport bus, the pump assembly including: a pump; and a pump protection device positioned below the pump along the vertical direction.

Abstract: A method of regulating pressure in a thermal transport bus of a gas turbine engine, the method including: operating the gas turbine engine with the thermal transport bus having an intermediary heat exchange fluid flowing therethrough, the thermal transport bus including one or more heat source heat exchangers and one or more heat sink heat exchangers in thermal communication through the intermediary heat exchanger fluid; and adjusting a flow volume of the thermal transport bus using a variable volume device in fluid communication with the thermal transport bus in response to a pressure change associated with the thermal transport bus.

Abstract: A propulsion system for an aircraft having an aft end is provided herein. The propulsion system can include an electric propulsion engine defining a central axis. The electric propulsion engine can include an electric motor, a fan rotatable about the central axis of the electric propulsion engine by the electric motor, a bearing supporting rotation of the fan, and a thermal management system. The thermal management system can include a lubrication oil circulation assembly for providing the bearing with lubrication oil. The lubrication oil circulation assembly can be driven independently of a shaft of the electric propulsion engine.

Abstract: Provided are systems and methods for decomposing learned robotic activities into smaller sub-activities that can be used independently. In one example, a method may include storing simulation data comprising an activity of a robot during a training simulation performed via a robotic simulator, decompose the activity into a plurality of sub-activities that are performed by the robot during the training simulation based on changes in behavior of the robot identified within the simulation data, and generating and storing a plurality of programs for executing the plurality of sub-activities, respectively, in the storage.

Abstract: A turbofan engine is provided. The turbofan engine includes a fan comprising a plurality of rotatable fan blades, each fan blade defining a fan tip speed; a turbomachine operably coupled to the fan for driving the fan, the turbomachine comprising a compressor section, a combustion section, and a turbine section in serial flow order and together defining a core air flowpath; and a gear box, wherein the turbomachine is operably coupled to the fan through the gear box, wherein a gear ratio of the gear box is greater than or equal to 1.2 and less than or equal to 3.0; wherein during operation of the turbofan engine at a rated speed the fan tip speed is greater than or equal to 1000 feet per second. In exemplary embodiments, during operation of the turbofan engine at the rated speed the fan pressure ratio is less than or equal to about 1.5.

Abstract: A turbine engine that includes an engine core, an inner cowl, an outer cowl and an accessory gearbox. The engine core includes at least a compressor section, a combustion section, and a turbine section in axial flow arrangement. The accessory gearbox is operably coupled to the engine core and includes a first portion and a second portion.

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 of detecting an airflow fault condition in a gas turbine engine, the method including: operating the gas turbine engine with a thermal transport bus having an intermediary heat exchange fluid flowing therethrough; determining a performance characteristic of the intermediary heat exchange fluid in the thermal transport bus is outside of a predetermined range, wherein the performance characteristic includes a temperature, a pressure, a flowrate, or a combination thereof; and indicating an airflow fault condition in response to determining the performance characteristic is outside of the predetermined range.

Abstract: A method of regulating pressure in a thermal transport bus of a gas turbine engine, the method including: operating the gas turbine engine with the thermal transport bus having an intermediary heat exchange fluid flowing therethrough, the thermal transport bus including one or more heat source heat exchangers and one or more heat sink heat exchangers in thermal communication through the intermediary heat exchanger fluid; and adjusting a flow volume of the thermal transport bus using a variable volume device in fluid communication with the thermal transport bus in response to a pressure change associated with the thermal transport bus.

Abstract: A propulsion system is provided including an unducted rotating fan defining a fan axis; and a turbomachine disposed downstream from the unducted rotating fan, wherein the turbomachine defines a working gas flowpath flowing therethrough; wherein the propulsion system defines a third stream flowpath and an inlet passage having an inlet that is offset from the fan axis, wherein the inlet passage is configured to provide an inlet airflow to the working gas flowpath, and wherein the third stream flowpath bypasses at least a portion of the turbomachine.

Abstract: A gas turbine engine having a waste heat recovery system is provided. The gas 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, the exhaust section including a primary exhaust flowpath and a waste heat recovery flowpath parallel to the primary exhaust flowpath; and the waste heat recovery system includes a heat source exchanger positioned in thermal communication with a first portion of the waste heat recovery flowpath.

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 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: A turbofan engine is provided. The turbofan engine includes a fan comprising a plurality of fan blades; a turbomachine operably coupled to the fan for driving the fan, the turbomachine comprising a compressor section, a combustion section, and a turbine section in serial flow order and together defining a core air flowpath; a nacelle surrounding and at least partially enclosing the fan; an inlet pre-swirl feature located upstream of the plurality of fan blades, the inlet pre-swirl feature attached to or integrated into the nacelle; and a means for reducing ice buildup or ice formation on the inlet pre-swirl feature, the means in communication with the inlet pre-swirl feature.