Abstract: An embodiment of a method includes depositing a quantity of first intermediary material onto an electrically insulating substrate in a pattern corresponding to a desired pattern of a first conductive structure. The first intermediary material is adhered to the substrate to form a first intermediate layer to maintain the desired pattern of the first conductive structure. A quantity of a precursor of electrically conductive material is deposited generally along the pattern of the first intermediate layer. Energy is applied to enable migration and consolidation of the first electrically conductive material along the pattern of the first intermediate layer, forming a functional, electrically conductive top layer. At least one of the first electrically conductive material and its precursor has a wetting angle of less than 90° relative to the first intermediate layer, and a wetting angle greater than 90° relative to the substrate. At least one of the depositing steps is an additive deposition step.

Abstract: A method includes detecting a failure in a contactor economizer that is configured to provide a first current to a coil of a contactor to close the contactor, and to provide a second current lower than the first current to the coil after the contactor is closed to hold the contactor closed. The method includes at least one of: driving contactor actuation based on economizer failure status; and/or signaling failure of the economizer through built in test (BIT) indication.

Abstract: In accordance with at least one aspect of this disclosure, a system includes a heat sink. In embodiments, the heat sink can include, a fin body, having a first face and a second face, one or more fins extending vertically from the fin body, and a clip disposed on one of the first face and/or the second face configured to attach to a heat generating component of a LRU to dissipate heat energy from the heat generating component of the LRU to an ambient environment. In embodiments, the heat generating component can include a bus bar, for example.

Abstract: A method of DC-DC power conversion includes converting a DC link voltage to a DC output voltage for a load that is lower than the DC link voltage using a buck converter. The method includes controlling the buck converter in a normal switching mode in response to the DC link voltage being below a predetermined high threshold. The method also includes controlling the buck converter in a soft start switching mode in response to the DC link voltage being at or above the predetermined high threshold.

Abstract: A conductor shielding termination assembly can include a housing tube defining an inner diameter housing channel therethrough and having housing threads on an outer diameter thereof. The housing tube can be made of conductive material. The assembly can include a shoulder bushing configured to insert within the inner diameter housing channel of the housing tube. The shoulder bushing can define an inner diameter bushing channel sized to receive an unshielded portion of a conductor. The assembly can include a jam nut comprising a nut inner diameter channel sized to receive a shielded portion of the conductor and nut threads on an inner diameter thereof configured to mesh with the housing threads. The jam nut and housing tube can be configured to trap a shielding termination within the meshed housing threads and jam nut threads.

Abstract: A complex concentrated alloy (CCA) and/or high entropy alloy (HEA) additive manufacturing nozzle can include a nozzle body defining at least four powder channels. Each powder channel can be configured to be connected to a powder supply of a plurality of powder supplies to receive a powder from the powder supply for ejecting the powder toward a build area to form an additively manufactured article having a CCA and/or an HEA.

Abstract: A method of DC-DC power conversion includes converting a DC link voltage to a DC output voltage for a load that is lower than the DC link voltage using a buck converter. The method includes controlling the buck converter in a normal switching mode in response to the DC link voltage being below a predetermined high threshold. The method also includes controlling the buck converter in a rate limited switching mode in response to the DC link voltage being at or above the predetermined high threshold.

Abstract: A conductor shielding termination assembly can include a housing tube defining an inner diameter housing channel therethrough. The housing tube can be made of conductive material. The assembly can include a shoulder bushing configured to insert within the inner diameter housing channel of the housing tube. The shoulder bushing can define an inner diameter bushing channel sized to receive an unshielded portion of a conductor. The assembly can include a clamping assembly configured to clamp around the housing tube and/or the conductor to axially lock the housing tube and the conductor and to trap a shielding termination between the housing tube and the clamping assembly. The clamping assembly can form a clamping inner diameter channel sized to receive a shielded portion of the conductor.

Abstract: In accordance with at least one aspect of this disclosure, a method of making a carbon rotor includes, providing a quantity of material, densifying the quantity of material, and forming the densified material into a disk shape.

Abstract: A method includes pumping coolant into a cooling system of a generator while the generator is generating electrical power. The method includes regulating flow into the cooling system using a pressure relief valve to recirculate a portion of the coolant back to an inlet of the pump. Using the pressure relief valve includes actuating the pressure relief valve based on input from the cooling system and/or from the generator.

Abstract: An environmental control system includes a refrigerant circuit with a pump segment and an evaporator segment, an evaporator arranged along the evaporator segment and in fluid communication with of the refrigerant circuit, and a coolant circuit. The coolant circuit extends through the evaporator and is thermally coupled to refrigerant circuit by the evaporator, the coolant circuit including a first segment and a second segment arranged in parallel with one another to transfer heat from a first zone to a first portion of liquid coolant traversing the coolant circuit and transfer additional heat from a second zone to a second portion of coolant traversing the coolant circuit. Aircraft and environmental control systems are also described.

Abstract: An airplane is provided. The airplane includes an environmental control system coupled to an engine and an inlet. The engine provides a bleed. The inlet provides a fresh medium. The environmental control system includes a compressing device comprising a compressor and a turbine. The environmental control system also includes a moisture removal circuit that separately removes moisture from each of the first and second mediums prior to combining the first medium and the second medium to form mixed air.

Abstract: An environmental control system is provided including a ram air circuit having a ram air duct and at least one heat exchanger arranged within the ram air duct. The ram air duct is curved about a ram axis. A compression device includes a compressor and at least one turbine operably coupled by a shaft rotatable about a shaft axis. The ram axis is arranged coaxially with the shaft axis.

Abstract: A fuel tank inerting system is provided including an air flow comprising air from a first source having a first temperature and air from a second source having a second temperature. The second temperature is cooler than the first temperature. At least one separating module is configured to separate an inert gas from the air flow.

Abstract: A thermal management system includes a closed-circuit refrigeration system that includes a vapor cycle system (VCS) and a liquid pumping system (LPS). The VCS includes a receiver that stores a refrigerant fluid and a liquid separator. The vapor cycle system is configured to operate in one or more operational modes including at least one of a TES cooling mode, a heat load cooling mode, or a pump-down mode. The LPS includes a thermal energy storage (TES) that stores a phase change material (PCM) and a pump fluidly coupled to at least one evaporator. The evaporator is configured to extract heat from a heat load that is in thermal conductive or convective contact to the evaporator to transfer heat to the refrigerant fluid and provide the refrigerant fluid from an evaporator outlet to the TES.

Abstract: A heat exchanger arrangement includes walls defining at least two circuit passages for porting a first fluid, a first of the circuit passages defining a first passage length, and a second of the circuit passages defining a second passage length, the second passage length being different from the first passage length, the walls being in thermal communication with a second fluid while isolating the first fluid from the second fluid, at least one of the first circuit passage and the second circuit passage includes a flow control feature configured to decrease an imbalance in flow between the first circuit passage and the second circuit passage compared to if the flow control feature were not present.

Abstract: A valve having a first segment between a first outer wall and a first inner wall and has a first outer port near the first outer wall and a side port between the first inner and outer walls; a second segment between a second outer wall and a second inner wall and has a second outer port near the second outer wall; a center segment between the first and second inner walls, and a center port; and a piston within the valve, having: a first piston head in the first segment that slides to block and unblock the side port; a second piston head in the second segment that slides between the second inner and outer walls, the second piston head having a surface area that is the same as the first piston head; and a shaft connecting the first and second piston heads.

Abstract: A heat exchanger core includes a first hollow cylinder extending circumferentially around a center axis and extending axially along the center axis. The first hollow cylinder includes a first passage disposed radially within the first hollow cylinder and extending axially through the first hollow cylinder. A second hollow cylinder extends circumferentially around the center axis and extends axially along the center axis. The first hollow cylinder is disposed radially within the second hollow cylinder. The second hollow cylinder includes a second passage disposed radially between the first hollow cylinder and the second hollow cylinder and extending axially between the first hollow cylinder and the second hollow cylinder. The first hollow cylinder fluidically separates the first passage from the second passage. The first and second hollow cylinders and the first and second passages are spaced from one another in a sinusoidal relationship.

Abstract: An air cycle machine includes an air inlet connected to an air cycle compressor. Air downstream of the air cycle compressor is connected to be delivered across a first turbine. The air cycle compressor is driven by the first turbine through a shaft. Air downstream of the first turbine is connected to a second turbine. The second turbine is connected to deliver air downstream. The second turbine is connected with a second shaft to drive a fan rotor. The fan rotor delivers a source of air across a primary heat exchanger positioned between the inlet and the air cycle compressor. The air cycle compressor and the first turbine are formed of a metal. The second turbine and the fan rotor are formed of non-metallic materials.

Abstract: A machine learning system that includes one or more machine learning models implemented in one or more hardware processors, a first-level feature creation module, and a combination module provides an output based on one or more channel inputs. Each of the one or more machine learning models receives the channel inputs and additional feature inputs based on the channel inputs to produce the output. The first-level feature creation module receives the channel inputs, performs a feature creation operation, creates the additional feature inputs, and provides the additional feature inputs to at least one of the machine learning models. The first-level feature creation operation performs a calculation on one or more aspects of the channel inputs, and the combination module receives the one or more machine learning model outputs and produce a machine learning channel output.