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 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 passive flow modulation device for a machine defining an axial direction and a radial direction, the passive flow modulation device including: a first ring with a first coefficient of thermal expansion; a second ring disposed coaxially with the first ring and positioned at least partially inward of the first ring along the radial direction, spaced from the first ring along the axial direction, or both, the first ring, the second ring, or both defining at least in part one or more passages, the second ring with a second coefficient of thermal expansion that is less than the first coefficient of thermal expansion to passively modulate a size of the one or more passages during operation.

Abstract: A gas turbine engine is provided including a turbomachine having a compressor section, a combustion section, and a turbine section arranged in serial flow order; a rotor assembly driven by the turbomachine, the rotor assembly, the turbomachine, or both comprising a substantially annular duct relative to the centerline of the gas turbine engine, the annular duct defining a flowpath; a heat exchanger positioned within the annular duct and extending substantially continuously along the circumferential direction, the heat exchanger comprising a first material defining a heat exchange surface exposed to the flowpath, wherein the first material defines a heat exchange coefficient and wherein the heat exchange surface defines a surface area (A), and wherein the heat exchanger has an effective transmission loss (ETL) of between 5 decibels and 1 decibel for an operating condition.

Abstract: Systems and methods of operating systems are provided. For example, a system comprises a fuel cooling loop including a cold fuel flowpath having a fuel flowing therethrough, a fuel cooler heat exchanger for cooling the fuel in fluid communication with the cold fuel flowpath, and a cold fuel tank disposed along the cold fuel flowpath for accumulating at least a portion of the cooled fuel. The system further comprises a fuel heating loop including a hot fuel flowpath for a flow of the fuel, a fuel heater heat exchanger for heating the fuel in fluid communication with the hot fuel flowpath, and a hot fuel tank disposed along the hot fuel flowpath for accumulating at least a portion of the heated fuel. The fuel cooling loop is coupled to the fuel heating loop such that the fuel circulates through both the fuel cooling loop and the fuel heating loop.

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: 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: Provided are fluid exchange apparatuses and methods of exchanging fluids between streams. Exemplary fluid exchange apparatus includes a first interleaved pathway with a plurality of first passages, and a second interleaved pathway with a plurality of second passages, in which the plurality of first passages and the plurality of second passages interleave with one another. Exemplary methods include directing a first fluid through a first interleaved pathway of a fluid exchange apparatus and directing a second fluid through a second interleaved pathway of a fluid exchange apparatus. The first fluid may flow from an upstream portion of a first duct into the first interleaved pathway and may discharge into a downstream portion of the second duct. The second fluid may flow from an upstream portion of the second duct into the second interleaved pathway and may discharge into a downstream portion of the first duct.

Abstract: An aspect of the present disclosure is directed to a system for reducing thermal gradient at a heat engine. The heat engine includes a rotor assembly with a rotor disk and a seal assembly is provided. An interfacing structure at least partially surrounds the rotor assembly at the seal assembly. The seal assembly and the interfacing structure together form a first cavity defining a first environmental condition and a second cavity defining a second environmental condition. A fluid supply manifold is connected to the rotor assembly and is extended at least partially along a radial direction from the first cavity to an outlet opening in thermal communication with the rotor disk of the rotor assembly.

Abstract: Dynamic directory service object creation and certificate management can be performed. In response to discovering a device connected to a network, a corresponding directory service object can be automatically created, and a digital certificate can be automatically acquired and deployed on the device to facilitate authentication. Further, actions can be logged, and notifications generated based on logged actions. Time involved in deploying and configuring directory services is reduced, efficiency is improved, and there is less of a chance for errors associated with manual configuration.

Abstract: A heat transfer system includes a heat exchanger located at least partially within a coolant flowpath. The heat exchanger defines at least in part a first flowpath and a second flowpath, the first flowpath configured to be in fluid communication with the coolant flowpath, and the second flowpath configured to receive a flow of a motive fluid. The heat transfer system further includes a throttling device that is in fluid communication with the second flowpath of the heat exchanger. The heat exchanger receives at least a portion of the flow of the motive fluid from the heat exchanger. The throttling device is also in fluid communication with the coolant flowpath at a location upstream of the heat exchanger for providing the flow of motive fluid to the coolant flowpath at the location upstream of the heat exchanger.

Abstract: Flow paths and boundary layer restart features are provided. For example, a flow path comprises a flow path wall defining an inner flow path surface and an asymmetric notch defined in the flow path wall. The asymmetric notch comprises a first surface and a second surface and is asymmetric about a first line extending through an intersection of the first and second surfaces. Further, a flow boundary layer restart feature comprises a first surface extending inward with respect to a flow path surface of a flow path and a second surface extending inward with respect to the flow path surface. The second surface is asymmetric with respect to the first surface such that the first and second surfaces define an asymmetric notch. Additionally, a flow path wall may comprise an asymmetric notch that includes a flow expansion angle and a flow contraction angle that are unequal.

Abstract: Systems and methods for operating systems are provided. For example, a system comprises a coolant flowpath having a coolant flowing therethrough, a cooling system for cooling the coolant disposed along the coolant flowpath, a fuel flowpath having a fuel flowing therethrough, a heat exchanger fluidly connected to the coolant flowpath and the fuel flowpath for heat transfer between the coolant and the fuel to cool the fuel, and a fuel tank for accumulating the cooled fuel. The fuel is in thermal communication with a first thermal load to cool the load. An exemplary method comprises flowing a heat exchange fluid along a flowpath; flowing a fuel along a fuel flowpath including a fuel tank; passing both the heat exchange fluid and fuel through a heat exchanger to cool the fuel; and controlling the fuel flow from the heat exchanger to the fuel tank for accumulation of the cooled fuel.

Abstract: A system for cooling aircraft components includes a compressor configured to receive air bled from a gas turbine engine and compress the received air. Additionally, the system includes a heat exchanger configured to receive the compressed air from the compressor and cool the compressed air; a turbine configured to receive the cooled air from the heat exchanger, with the cooled air expanding as the cooled air flows through the turbine. Furthermore, the system includes a defroster configured to receive the expanded air from the turbine, with the defroster further configured to capture frozen particulate matter from the expanded air. As such, at least a portion of the cooled air from the heat exchanger is routed to the defroster to melt the captured frozen particulate matter.

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: In an embodiment, a heat exchanger includes a monolithic body that includes a first substrate, a second substrate, a third substrate, and a plurality of partial height fins. The second substrate is arranged parallel to and spaced from the first substrate, thereby defining a first fluid flow path. The third substrate is arranged parallel to and spaced from the second substrate opposite the first substrate, thereby defining a second fluid flow path. The plurality of partial height fins extend from one of the second substrate and the third substrate toward the other of the second substrate or the third substrate, wherein a terminal edge of each partial height fin is at least partially spaced from the other of the second substrate or the third substrate.

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: The present disclosure provides fluid eductors, systems that utilize fluid eductors, and methods of entraining a suction fluid flow using a fluid eductor. Exemplary fluid eductors include a concentric eductor space or a plurality of annular eductor spaces. Exemplary methods include ejecting a volume of motive fluid out of a concentric eductor space of a fluid eductor, accelerating a peripheral region of the suction fluid flow with the motive fluid ejecting out of the first annular eductor space, and accelerating a core region of the suction fluid flow with the motive fluid ejecting out of the second annular eductor space.

Abstract: Provided are fluid exchange apparatuses and methods of exchanging fluids between streams. Exemplary fluid exchange apparatus includes a first interleaved pathway with a plurality of first passages, and a second interleaved pathway with a plurality of second passages, in which the plurality of first passages and the plurality of second passages interleave with one another. Exemplary methods include directing a first fluid through a first interleaved pathway of a fluid exchange apparatus and directing a second fluid through a second interleaved pathway of a fluid exchange apparatus. The first fluid may flow from an upstream portion of a first duct into the first interleaved pathway and may discharge into a downstream portion of the second duct. The second fluid may flow from an upstream portion of the second duct into the second interleaved pathway and may discharge into a downstream portion of the first duct.

Abstract: A system for energy conversion is provided including a propulsion system, a fuel circuit, a combustion device and turbine separate from the propulsion system, and a load device. A fuel flow control device separates a flow of fuel from the fuel tank into a first portion of fuel and a second portion of fuel. A fuel circuit is configured to provide the first portion of fuel to a heat addition system at the propulsion system. A combustion device receives a flow of oxidizer from a compressor section of the propulsion system via a fluid circuit. The fuel circuit provides the second portion of fuel to the combustion device. The fluid circuit flows combustion gases to the turbine and the propulsion system. The load device is operably coupled to the turbine to receive an output torque via expansion of the combustion gases through the turbine.